AFTV - Audio Drift on KSNV

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kingcoldcuts
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AFTV - Audio Drift on KSNV

Post by kingcoldcuts »

This could be caused by the way my audio chain is setup, but thought it was worth mentioning in case someone has suggestions for troubleshooting:

Device: HDHomeRun Flex 4K
Playback Device: Amazon Fire TV Stick 4K Max Gen 2
AVR: Denon AVR-S740H
Firmware: Latest
Software: Latest
Behavior: Audio drift only on KSNV AC-4 Atmos track decoded natively by the AFTV device. Audio set to "Passthrough" in HDHomeRun app. Becomes noticeable before 20 minute mark. It can be hard to pin down the timeframe as I am usually watching sports when it happens, so there's not much dialogue to match up on the screen for long periods at a time. Does not happen when audio is transcoded. Does not happen with 2017 Nvidia Shield Pro with all the same equipment (obviously that device is not sending passthrough because the Shield doesn't decode AC-4 natively). Does not happen on other channels with non-Atmos audio tracks.

Let me know if you guys ever want any data or additional information.

Thanks!

jasonl
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Re: AFTV - Audio Drift on KSNV

Post by jasonl »

Does this happen on both live TV and recordings? If it happens on recordings, we'd like to get a copy of one of them for our engineering team to review.

nickk
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Re: AFTV - Audio Drift on KSNV

Post by nickk »

The Amazon Fire TV Stick 4K Max Gen 2 has built in AC4 support. If the A/V sync is drifting it may be an issue with the built in codec.

kingcoldcuts
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Re: AFTV - Audio Drift on KSNV

Post by kingcoldcuts »

jasonl wrote: Mon Dec 15, 2025 7:17 pm Does this happen on both live TV and recordings? If it happens on recordings, we'd like to get a copy of one of them for our engineering team to review.
Unfortunately, I don't have a DVR account (yet!). I can only speak to the live broadcasts.

kingcoldcuts
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Re: AFTV - Audio Drift on KSNV

Post by kingcoldcuts »

nickk wrote: Mon Dec 15, 2025 9:13 pm The Amazon Fire TV Stick 4K Max Gen 2 has built in AC4 support. If the A/V sync is drifting it may be an issue with the built in codec.
Thanks! Makes sense. I'll leave them some feedback.

howardc1243
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Re: AFTV - Audio Drift on KSNV

Post by howardc1243 »

nickk wrote: Mon Dec 15, 2025 9:13 pm The Amazon Fire TV Stick 4K Max Gen 2 has built in AC4 support. If the A/V sync is drifting it may be an issue with the built in codec.
there may also be a misconfig in the codec relating to the audio handler of the Amazon fire tv.

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