Recording glitches with Expand/Synology DS214+

Reception, channel detection, network issues, CableCARD setup, etc.
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Jantje
Posts: 8
Joined: Thu Jun 20, 2019 11:52 am

Recording glitches with Expand/Synology DS214+

Post by Jantje » Thu Jun 20, 2019 11:57 am

Hi,

my setup is a Synology NAS DS214+ with TV Mosaic and a quad tuner HD HomeRun Expand.
The recordings almost all contain graphical glitches. Happens every minute or so for a few seconds. Same in VLC so it's the recording file which contain the glitches. When playing you will see big green-like blocks which are not that problematic... I can live with that BUT sometimes it also creates high audio pitch sounds which are very annoying.
My coax signal is 100% and when viewing this coax signal like normal on my TV (not through Kodi or HD HomeRun) the pictures are 100% correct.

On this page http://192.168.11.105/lineup.html I found all my HDHomeRun channels with direct playlink.
I played http://192.168.11.105:5004/auto/v1 stream directly in VLC and after a minute or so I also got graphical glitches.

Do other have the same setup which do not experience these recording glitches?
Any tips on how to fix or workaround this?

goofnroxx
Posts: 75
Joined: Fri Jun 16, 2017 10:30 am

Re: Recording glitches with Expand/Synology DS214+

Post by goofnroxx » Thu Jun 20, 2019 1:18 pm

I would guess TV mosaic uses UDP to stream from the tuner, and packets are getting dropped occasionally. I used to see this frequently running a MythTV backend from a NAS. I never figured it out at the time, but some research since then suggests increasing the network buffers, if that's even possible on a Synology NAS. Since switching to the SD-DVR, recordings are glitch free on the same hardware for me, which uses TCP if i'm not mistaken, and less prone to dropped packets.

jasonl
Silicondust
Posts: 14233
Joined: Sun Oct 28, 2007 9:23 pm

Re: Recording glitches with Expand/Synology DS214+

Post by jasonl » Thu Jun 20, 2019 1:20 pm

Please enable the sending of diagnostic data on the HDHomeRun and run a channel scan (see viewtopic.php?f=15&t=69066) then watch live TV on a problem channel in VLC or the HDHomeRun app until you see a glitch and for at least 10 minutes after that. Reply back with the device ID for your HDHomeRun and we will check the logs.

Jantje
Posts: 8
Joined: Thu Jun 20, 2019 11:52 am

Re: Recording glitches with Expand/Synology DS214+

Post by Jantje » Thu Jun 20, 2019 11:02 pm

goofnroxx wrote:
Thu Jun 20, 2019 1:18 pm
I would guess TV mosaic uses UDP to stream from the tuner, and packets are getting dropped occasionally. I used to see this frequently running a MythTV backend from a NAS. I never figured it out at the time, but some research since then suggests increasing the network buffers, if that's even possible on a Synology NAS. Since switching to the SD-DVR, recordings are glitch free on the same hardware for me, which uses TCP if i'm not mistaken, and less prone to dropped packets.
Thanks for your reply... took a look in my DSM settings to look for network buffer settings, but the only network related setting I can change is MTU value. Need todo more research on that topic though.
What exactly is SD-DVR? Where can I find this software/product??

Jantje
Posts: 8
Joined: Thu Jun 20, 2019 11:52 am

Re: Recording glitches with Expand/Synology DS214+

Post by Jantje » Thu Jun 20, 2019 11:04 pm

jasonl wrote:
Thu Jun 20, 2019 1:20 pm
Please enable the sending of diagnostic data on the HDHomeRun and run a channel scan (see viewtopic.php?f=15&t=69066) then watch live TV on a problem channel in VLC or the HDHomeRun app until you see a glitch and for at least 10 minutes after that. Reply back with the device ID for your HDHomeRun and we will check the logs.
Ok thanks, will do sometime in the coming days, probably next monday... currently busy.

goofnroxx
Posts: 75
Joined: Fri Jun 16, 2017 10:30 am

Re: Recording glitches with Expand/Synology DS214+

Post by goofnroxx » Fri Jun 21, 2019 5:33 am

Jantje wrote:
Thu Jun 20, 2019 11:02 pm
goofnroxx wrote:
Thu Jun 20, 2019 1:18 pm
I would guess TV mosaic uses UDP to stream from the tuner, and packets are getting dropped occasionally. I used to see this frequently running a MythTV backend from a NAS. I never figured it out at the time, but some research since then suggests increasing the network buffers, if that's even possible on a Synology NAS. Since switching to the SD-DVR, recordings are glitch free on the same hardware for me, which uses TCP if i'm not mistaken, and less prone to dropped packets.
Thanks for your reply... took a look in my DSM settings to look for network buffer settings, but the only network related setting I can change is MTU value. Need todo more research on that topic though.
What exactly is SD-DVR? Where can I find this software/product??
Silicons Dust's DVR. https://www.silicondust.com/dvr-service/

Those type of network settings are unlikely to be exposed in the GUI interface. Most likely it would be a SSH and command line if it's possible.

Jantje
Posts: 8
Joined: Thu Jun 20, 2019 11:52 am

Re: Recording glitches with Expand/Synology DS214+

Post by Jantje » Fri Jun 21, 2019 2:13 pm

Thanks did not realise SD in SD-DVR was of course Silicon Dust duh :)

Currently reading
https://jvns.ca/blog/2016/08/24/find-ou ... g-packets/
and
https://blog.packagecloud.io/eng/2016/0 ... -rx-queues

to adjust receiving (RX) networkbuffers which are used by udp packets. When to small and/or data is coming in too fast UDP packets gets dropped.
Hopefully I can adjust it... keep u posted

Jantje
Posts: 8
Joined: Thu Jun 20, 2019 11:52 am

Re: Recording glitches with Expand/Synology DS214+

Post by Jantje » Fri Jun 21, 2019 2:36 pm

Arghh almost nothing is supported, can't change any parameters... I get operation not supported:
# sudo ethtool -i eth0
driver: mv_eth
version:
firmware-version: N/A
bus-info: Mbus
supports-statistics: no
supports-test: no
supports-eeprom-access: no
supports-register-dump: yes
supports-priv-flags: no

# sudo ethtool -g eth0
Ring parameters for eth0:
Pre-set maximums:
RX: 0
RX Mini: 0
RX Jumbo: 0
TX: 0
Current hardware settings:
RX: 0
RX Mini: 0
RX Jumbo: 0
TX: 0

# sudo ethtool -p eth0
Cannot identify NIC: Operation not supported

# sudo ethtool -e eth0
Cannot get EEPROM data: Operation not supported

# sudo ethtool -k eth0
Features for eth0:
rx-checksumming: on [requested off]
tx-checksumming: on
tx-checksum-ipv4: on
tx-checksum-unneeded: off
tx-checksum-ip-generic: off
tx-checksum-ipv6: off
tx-checksum-fcoe-crc: off [fixed]
tx-checksum-sctp: off [fixed]
scatter-gather: on
tx-scatter-gather: on
tx-scatter-gather-fraglist: off [fixed]
tcp-segmentation-offload: on
tx-tcp-segmentation: on [requested off]
tx-tcp-ecn-segmentation: off
tx-tcp6-segmentation: off
udp-fragmentation-offload: off [fixed]
generic-segmentation-offload: on
generic-receive-offload: on
large-receive-offload: off [fixed]
rx-vlan-offload: off [fixed]
tx-vlan-offload: off [fixed]
ntuple-filters: off [fixed]
receive-hashing: off [fixed]
highdma: off [fixed]
rx-vlan-filter: off [fixed]
vlan-challenged: off [fixed]
tx-lockless: on [fixed]
netns-local: off [fixed]
tx-gso-robust: off [fixed]
tx-fcoe-segmentation: off [fixed]
fcoe-mtu: off [fixed]
tx-nocache-copy: on
loopback: off [fixed]

# sudo ethtool eth0
Settings for eth0:
Supported ports: [ TP MII ]
Supported link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Full
Supported pause frame use: No
Supports auto-negotiation: Yes
Advertised link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Half 1000baseT/Full
Advertised pause frame use: No
Advertised auto-negotiation: No
Link partner advertised link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Half 1000baseT/Full
Link partner advertised pause frame use: No
Link partner advertised auto-negotiation: Yes
Speed: 1000Mb/s
Duplex: Full
Port: MII
PHYAD: 1
Transceiver: internal
Auto-negotiation: on
Supports Wake-on: g
Wake-on: d
Link detected: yes

Jantje
Posts: 8
Joined: Thu Jun 20, 2019 11:52 am

Re: Recording glitches with Expand/Synology DS214+

Post by Jantje » Thu Aug 15, 2019 1:12 pm

Ok finally I know some more about my problem. I now narrowed it down and got it down to the following:

after a long period time (power of the hdhome run was always on and I do multiple recordings ~5 per day with some other third party software) of use (don't know the exact number of days/weeks) the signal quality (not strength!) and symbol quality goes way down to like 30%-50%. If I use the same input source DVB-C signal from the hdhome run device on my TV everything is ok. Mind you not the output of the hdhome run device which is a network stream!
I then made sure, by checking http://192.168.x.y/tuners.html , that no tuners where in use. Then I try to play a stream (RTL 5 HD) in VLC (I copied the url from http://192.168.x.y/lineup.html ): I get all green blocks or even total blackness for multiple seconds. I then *only* repowered the HDHomeRun EXPAND by unplugging and replugging the powercable and voila everything back to 100% quality and everything works!

My workaround for now is power recycle the device every day. Is there a way to automate this, can you reboot from a script or something? Meanwhile I will monitor the problem and try to power recycle every week, then every month, etc... to figure out what the max. period of power on time the problem re-occurs. Maybe it's a memory leak or something? Maybe Silicon Dust can setup same box and put it on always and do some recordings now and then and check the quality of it after long(er) periods of time.

I made a script that automatically monitors http://192.168.x.y/tuners.html?page=tunerX pages for drop in quality and notify me by sending a push notification so I get instant feedback when problems occur. Every time I get a drop in quality I will log the days interval and reboot the device. If the interval stays the same it is clearly a software bug, if not then it still can be a software bug but then I have to do some more digging. I will report back here.

Btw: I use the latest Firmware: 20190621

jasonl
Silicondust
Posts: 14233
Joined: Sun Oct 28, 2007 9:23 pm

Re: Recording glitches with Expand/Synology DS214+

Post by jasonl » Thu Aug 15, 2019 2:29 pm

I would recommend you enable the sending of diagnostic data as I requested back in June. What you're seeing sounds like a hardware issue, and if we can confirm that, and the device is still under warranty, we will replace it.

Jantje
Posts: 8
Joined: Thu Jun 20, 2019 11:52 am

Re: Recording glitches with Expand/Synology DS214+

Post by Jantje » Fri Aug 16, 2019 1:33 am

jasonl wrote:
Thu Aug 15, 2019 2:29 pm
I would recommend you enable the sending of diagnostic data as I requested back in June. What you're seeing sounds like a hardware issue, and if we can confirm that, and the device is still under warranty, we will replace it.
thanks for the quick reply.
ok will do, but I have to wait till the problem re-occurs. Since I just restarted the device and now everything works again.. I think it will take a few weeks before it re-occurs.

I have still waranty... it's just 5 months old. How does this replacement procedure goes? Any costs?

I checked the first 10 seconds of the last 112 recordings (mostly SD recordings) from a period of exact (the last) one month (16 july - 16 aug). Of which 19 recordings were bugged, all were from 1 aug or later. But there were also good recordings in that period. I also could not spot a pattern (multiple recordings at the same time, or only bugged *HD* recordings, ...)

Btw:
- do I really have to do a rescan? I am afraid any settings in HD or TV Mosaic would get lost.
- is there a way to reboot the device by using a script or api call or something?
- the log thats gets send to you is that exact the same as when I view http://192.168.x.y/log.html ?

jasonl
Silicondust
Posts: 14233
Joined: Sun Oct 28, 2007 9:23 pm

Re: Recording glitches with Expand/Synology DS214+

Post by jasonl » Sun Aug 18, 2019 2:58 pm

If we determine that a replacement is needed, we'll have you open a ticket and will provide instructions on how to return the device. The only cost is you returning the original device to our distribution center in the UK.

A scan is needed so we can see what the overall signal level looks like on the line, just to make sure it's not something specific to that. Just based on the description of the issue I think it's probably a hardware issue with the HDHomeRun, but I need to rule out any other obvious suspects before we replace it.

You can reboot using the hdhomerun_config command line.
Windows:

Code: Select all

"%programfiles%\silicondust\hdhomerun\hdhomerun_config.exe" DEVICEID set /sys/restart self
Mac/Linux:

Code: Select all

hdhomerun_config DEVICEID set /sys/restart self
Use the actual device ID in place of DEVICEID.

The logs is more detailed than what is shown on the device's web page.

Jantje
Posts: 8
Joined: Thu Jun 20, 2019 11:52 am

Re: Recording glitches with Expand/Synology DS214+

Post by Jantje » Tue Aug 20, 2019 3:32 am

jasonl wrote:
Sun Aug 18, 2019 2:58 pm
If we determine that a replacement is needed, we'll have you open a ticket and will provide instructions on how to return the device. The only cost is you returning the original device to our distribution center in the UK.
ok thanks, since I am located in NL this will propably cost me some...
jasonl wrote:
Sun Aug 18, 2019 2:58 pm
A scan is needed so we can see what the overall signal level looks like on the line, just to make sure it's not something specific to that. Just based on the description of the issue I think it's probably a hardware issue with the HDHomeRun, but I need to rule out any other obvious suspects before we replace it.
The device works for weeks and then suddenly recordings went bad because(?) of bad signal based on my first findings / first case.
My logger program is running right now and it checks all tuners for recordings, stream info and signal stats (and calculating min/max/avg) by polling every minute using the hdhome_config tool and calling /debug and /streaminfo
All is saved in a simple database. I will sent it you after logging for some weeks.

Btw I already noticed some process checking every channel for 1-2 minutes. This is probably TV Mosaic scaning the DVB-C signal for EPG data or something.
jasonl wrote:
Sun Aug 18, 2019 2:58 pm
You can reboot using the hdhomerun_config command line.
Windows:

Code: Select all

"%programfiles%\silicondust\hdhomerun\hdhomerun_config.exe" DEVICEID set /sys/restart self
Mac/Linux:

Code: Select all

hdhomerun_config DEVICEID set /sys/restart self
Use the actual device ID in place of DEVICEID.
Great! IF it's power-on time related I can do a scheduled reboot every night or week or so as a potentially workaround.
Tip: this was not documented in https://www.silicondust.com/hdhomerun/h ... opment.pdf which btw seems outdated (2011-05-18). Where is the latest?
Also where can I find the net: stop reason code descriptions? I have seen values 0,1 and 4 but don't know what they mean, this is also not documented.
jasonl wrote:
Sun Aug 18, 2019 2:58 pm
The logs is more detailed than what is shown on the device's web page.
The log is very minimal. Would be nice if I could see more details and/or see what is actually sent to you... also from privacy / transparancy perspective.

jasonl
Silicondust
Posts: 14233
Joined: Sun Oct 28, 2007 9:23 pm

Re: Recording glitches with Expand/Synology DS214+

Post by jasonl » Tue Aug 20, 2019 12:17 pm

Stop codes:
0 - not stopped
1 - UDP/RTP stream stopped by application
2 - UDP/RTP stream stopped due to ICMP reject
3 - stream stopped due to network disconnect
4 - HTTP stream stopped due to connection being closed

The diagnostic data is the log data plus signal stats when channels are streaming.

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