Is there a debugging mode available in the HDHOMERUN player for Windows and Android to determine if I am decrypting AC4 or transcoding AC3 stereo through the SiliconDust server?
The reason I ask is I believe my Windows 11pro uses my AC4 codec with third party player as will with the HDHOMERUN player , but the HDHOMERUN player in Android is not finding my AC4 codec that is hidden away in my Amlogic S905y4 SoC (on my Android STB) and is being forced to the SiliconDust transcode service that only offers 2.0 stereo and not AC3 5.1 surround sound.
I have also tested my Android STB with a third party player ( I am appy to disclose but due to rules I don't want to post it) and the debug mode clearly shows the HEVC/AC4 codecs being used.
How does Amlogic get away with decoding AC4 without an official licensed HW and SW Dolby.AC4 codec?
ATSC 3.0 AC4 audio
Re: ATSC 3.0 AC4 audio
Which Android STB? Is it Dolby Atmos-licensed?
Re: ATSC 3.0 AC4 audio
I can't list it here due to forum rules. It is a Chinese Android 11 STB with a Sony Tuner and connects via HDMI.
The product clearly decodes AC4 , but if you run a codec search using Aida 64 you will find the HW and SW for HEVC but not Dolby.AC4 codecs. Amlogic has imbedded the AC4 codec in the SoC. Other tuner STBs operate in the same way. So no the STB does not have a licensed Dolby AC4 codec that is advertised or listed on the Dolby website for AC4.
I use this STB with the HDHOMERUN player to have my Flex 4k function.
The product clearly decodes AC4 , but if you run a codec search using Aida 64 you will find the HW and SW for HEVC but not Dolby.AC4 codecs. Amlogic has imbedded the AC4 codec in the SoC. Other tuner STBs operate in the same way. So no the STB does not have a licensed Dolby AC4 codec that is advertised or listed on the Dolby website for AC4.
I use this STB with the HDHOMERUN player to have my Flex 4k function.
Re: ATSC 3.0 AC4 audio
The Licensing Catch: Even though the chip architecture is capable of decoding AC-4, the specific device you purchase must have an active Dolby license.
Variant Suffixes: In retail media boxes, Amlogic chip variants featuring a "-H" or "-J" suffix (e.g., S905X4-J or S912-H) include the official commercial Dolby licenses required to activate hardware-level Dolby decoding. Standard or lower-cost variants omit the license to save on royalties, resulting in a lack of native AC-4 audio decoding.
Variant Suffixes: In retail media boxes, Amlogic chip variants featuring a "-H" or "-J" suffix (e.g., S905X4-J or S912-H) include the official commercial Dolby licenses required to activate hardware-level Dolby decoding. Standard or lower-cost variants omit the license to save on royalties, resulting in a lack of native AC-4 audio decoding.
Re: ATSC 3.0 AC4 audio
The Amlogic SoC in my STB is S905y4. I have a photo of this however there is an additional sticker on the motherboard that says YL905Y4-B which is a Dolby AC4 licensed product per a Google Search. I have proven beyond a shadow of doubt this box does decode AC4 using two player apps, but not all apps, however Aida 64 does not show the Dolby.ac4 codec.zippy wrote: Wed Sep 09, 2026 2:33 pm The Licensing Catch: Even though the chip architecture is capable of decoding AC-4, the specific device you purchase must have an active Dolby license.
Variant Suffixes: In retail media boxes, Amlogic chip variants featuring a "-H" or "-J" suffix (e.g., S905X4-J or S912-H) include the official commercial Dolby licenses required to activate hardware-level Dolby decoding. Standard or lower-cost variants omit the license to save on royalties, resulting in a lack of native AC-4 audio decoding.
Still hoping to see if there is a hidden debugging mode on both the windows and android clients.
Re: ATSC 3.0 AC4 audio
There is no customer-visible diagnostic mode, but if you enable the sending of diagnostic data in the gear menu HDHomeRun app, watch an ATSC 3.0 channel, and reply back with the device ID for your HDHomeRun, we can check the logs to see what AC-4 mode is in use.