Black screen with "Audio only", etc.

[leerandall]

When you turned the DVR back on on the MeCool box, did you turn off the PC DVR before testing? If not, it may still be using the PC DVR instead of the MeCool.

[PTSD]

Yes, I did turn off recording on the PC before re-enabling on the MeCool TV box.

I think the smoking gun here is the Video Quality options in the gear menu on the MeCool box that only appeared when I first disabled recording there. They went away after I re-enabled recording on the MeCool box and banged hard enough on local playback to get it in a frozen frame state. But it's quite possible that those Video Quality options are not intended to show up when recording is enabled? I am gonna do a bit more testing tonight around this...

[signcarver]

Those video quality settings show up when there is a detected (mpeg2) hardware decode error and it has to switch to software decode.

[NedS]

The app attempts to detect if the decoders are working, and some other stuff, so it might be that we need to set something manually for that specific box, rather than automatic detection.

[PTSD]

A few nights ago I reset the MeCool KM2 Plus TV box to factory defaults, re-installed HDHomeRun only, and updated the bundled apps via Google PlayStore. I've left Android Settings practically bone stock, only disabling WiFi, changing the "Standby mode definition" (aka power key function) from Sleep to Shutdown, and disabling HDMI CEC (since that would now shut down the box and prevent recordings).

I'm still not seeing those Video Quality settings in HDHomeRun, so I assume it believes that the hardware decoders are working correctly. However the black "Audio only" screen is still showing frequently when attempting to playback a recording.

This TV box is advertised as having an Amlogic S905X4-B SoC with quad core ARM Cortex-A55 @ 2.0GHz and Arm Mali-G31 MP2 Integrated GPU. AIDA64 basically confirms all that (but doesn't mention the SoC model number). AIDA64 says the CPU instruction set is "64-bit ARMv8-A (32-bit Mode)" and the Android kernel architecture is "armv8l".

The app attempts to detect if the decoders are working, and some other stuff, so it might be that we need to set something manually for that specific box, rather than automatic detection.

AIDA64 shows "OMX.amlogic.mpeg2.decoder.awesome2" as the only video/mpeg2 codec. What "other stuff"does HDHomeRun look for? What are you seeing in the Diagnostic data being sent to SiliconDust?

Is it possible to provide an HDHomeRun build that skips auto-detection? It's getting real old not being able to reliably watch recorded programs on the TV connected to the MeCool box...

[jasonl]

We can block specific device/codec/resolution combinations on the server side. Do you see the audio only message on 1080i (CBS, NBC), 720p (ABC, Fox), and/or 480i (most everything that isn't a major network)?

[Cabal]

Is page 2 too late to point out that the MeCool KM2 Plus is a garbage device and you should return it if you're still able? I tested out one of these for the native AC-4 support, and had no end to troubles with it, both MPEG-2 and elsewhere. Support was able to confirm the problems but could do nothing to fix them, and I ended up junking the device after wasting a bunch of time.

Happy to give recommendations elsewhere (specifically, the List of Supported Devices thread in the ATSC 3.0 forum).

[PTSD]

We can block specific device/codec/resolution combinations on the server side. Do you see the audio only message on 1080i (CBS, NBC), 720p (ABC, Fox), and/or 480i (most everything that isn't a major network)?

Thanks Jason. All recordings here are on the major networks' primary channels, so 1080i and 720p. But won't your block need to cover the entire device, since HDHomeRun settings are global (aren't they?) and not tied to the recording tasks for specific channels?

[PTSD]

Is page 2 too late to point out that the MeCool KM2 Plus is a garbage device and you should return it if you're still able? I tested out one of these for the native AC-4 support, and had no end to troubles with it, both MPEG-2 and elsewhere. Support was able to confirm the problems but could do nothing to fix them, and I ended up junking the device after wasting a bunch of time.

I've had this KM2 Plus for over a month and it's probably too late to return to Amazon. Seems to work fine for just streaming and I will keep it for that, even if SiliconDust can't engineer a workaround for the playback issue. It also has an unlockable bootloader so has some value for Android ROM hacking, etc.

Happy to give recommendations elsewhere (specifically, the List of Supported Devices thread in the ATSC 3.0 forum).

Thanks for the tip, I think I found the thread you mentioned here? viewtopic.php?t=77879

Second post there looks to be a list that has been updated at least once by nickk, but "Mecool KM2 Plus" is (still?) in the list. And there don't seem to be any other straight "Android TV" boxes in the list that are capable of recording via HDHomeRun, but I will take any recommendations you can give me, thanks.

My previous MECOOL KM9 Pro worked great for recording from my CONNECT QUATRO, but it suddenly gave up the ghost more than a month ago and is completely dead. Dummy me assumed a similar Android TV model with a newer OS and twice as many CPU cores running at a faster speed would be a worthwhile upgrade. But this recording playback bug has been nothing but annoying since I first set up the box. On the plus side (?) there's been about half a dozen OTA updates since the KM2 Plus first hit market (vs. a single update for the KM9 Pro), so perhaps there is (or will be) another update in the pipeline that may fix this playback issue?

In the meantime I've moved HDHomeRun recording functionality to an Intel NUC7PJYHN Mini PC running Windows 10. We are still using the MeCool KM2 Plus for playback and it seems to work OK that way, with no black "Audio only" screen. Programs previously recorded on the MeCool seem to have a slight audio lag when playing them back remotely from the Intel NUC. Not sure if this will happen with programs recorded directly on the NUC, but we'll know by tomorrow afternoon when the day's soap operas have been recorded there.

Edited to add: Having a second dedicated Windows box for recording is less than ideal as that device has issues of it's own. I hope that Jason can still pursue blocking hardware decoding for the MeCool KM2 Plus.

[Cabal]

The first page of that thread hasn't been kept up to date, unfortunately, but my preferred device is the SEI804 series (Homatics/Dune/RockTek/Nokia). I have replaced my Shield Pro with it, specifically a RockTek G2. Excellent device with AV1, AC-4, and it's fast. That model can regularly be found on sale for $109.

I think using Android to host the recording service is not recommended due to limitations related to external storage. I run my DVR service on a NAS, and if not that, I would plug directly into my Flex 4K.

Hope that helps.

[signcarver]

I haven't really seen android record function work well since Android 9... the newer the OS the more $%^# they put in it in the name of security that breaks everything. I had no problem with the mecool in question when I used it but I would never rely on an android device to run the dvr engine and consider such a novelty of proof of concept that it can work, not that it works reliably.

[foxbat121]

Video quality setting means HDHR app detected that your hardware decoder on the MeCool failed somehow and switched over to software decoder instead. It only means one thing: MeCool is not cool I personally will not trust this device to do anything right.

[PTSD]

The first page of that thread hasn't been kept up to date, unfortunately, but my preferred device is the SEI804 series (Homatics/Dune/RockTek/Nokia). I have replaced my Shield Pro with it, specifically a RockTek G2. Excellent device with AV1, AC-4, and it's fast. That model can regularly be found on sale for $109.

Thanks for the tip. I see this RockTek G2 at Amazon, currently selling for $149 (but will definitely consider purchasing if it drops down to $109):
https://www.amazon.com/Streaming-Certif ... B0BMLJ84LQ

I haven't really seen android record function work well since Android 9... the newer the OS the more $%^# they put in it in the name of security that breaks everything. I had no problem with the mecool in question when I used it but I would never rely on an android device to run the dvr engine and consider such a novelty of proof of concept that it can work, not that it works reliably.

I think using Android to host the recording service is not recommended due to limitations related to external storage. I run my DVR service on a NAS, and if not that, I would plug directly into my Flex 4K.

My MECOOL KM9 Pro ran Android 9.0 and seemed to have no problems reading or writing to external storage. I initially recorded to an installed 512 GB microSD card mounted as external storage (after formatting as exFAT on a PC). That worked fine for a couple of years but eventually the HDHomeRun logs were showing occasional indications of problems writing to the SD card. So I ended up swapping that with a 2.5" WD Black HDD in an external USB powered case. There were no problems recording with that setup either. Unfortunately the drive was being hard reset at every restart of the Android TV, and I suspect that transients eventually wiped out some of the power functions for the USB port and/or elsewhere in the device.

Anyway, the consensus here seems to be "don't use MECOOL (or any other Android TV box) for DVR storage". So I think I will just stick with using my Intel NUC7PJYHN as the HDHomeRun recording device. This NUC model has a Pentium Silver J5005 quad-core CPU (which is quite a bit beefier than the Celeron J3455 in my Synology NAS). It doesn't have an M.2 slot but I have a Samsung EVO 870 SSD installed in the 2.5" SATA drive bay. It has no problem streaming recordings previously made on the MECOOL KM2 Plus, and had no problems recording today's soap operas for the wife.

We are only using this setup for ephemeral recordings of daytime soaps and nightime musical competitions. No Kodi and no storage or hosting of photo albums or ripped DVDs etc. Seems like it will be Good Enough.

[nickk]

I set up a KM2 PLUS in the test lab - it is playing all our MPEG2 test streams from a Linux server ok.

[PTSD]

Our KM2 Plus also plays streams from remote hosts just fine, as confirmed by using my own Wintel PC for DVR storage, and now the Intel NUC Windows DVR I setup as a workaround. Just can't figure out why the KM2 Plus doesn't like playing .mpg files from it's own local filesystem.

With Android 9 on the older KM9 Pro that we were using (before it died) I always had the DVR storage formatted as exFAT and mounted as "external" i.e. removeable. Maybe that's what the KM2 Plus is tripping over, and maybe it would be better behaved if I formatted and mounted the storage in Android 11 as "internal" i.e. non-removeable?

I'm not sure if HDHomeRun will properly recognize the additional ~500 GB of space as available for DVR recording. But now that I'm more familiar with the whole client-server architecture for HDHomeRun DVR functionality I realize that I can just go ahead and test this...

Our previous recordings are now safely transferred to internal SATA storage on the Intel NUC and that host is working fine for primary recordings. I am going to reconnect the Plugable Technologies USBC-NVME enclosure to the KM2 Plus and format the storage as internal. Not sure what filesytem format Android 11 will use for that but hopefully it will work for DVR (testing at least).