Regression since v4.8 – Chromecast Gen2 stuttering when hardware acceleration (AMF) enabled

[glengrant 8]

Hello Emby Team,

I’ve been experiencing playback issues on my second-generation Chromecast for about two months, starting around April 2025, coinciding with the upgrade to version 4.8.x.

Here are my findings:

>> With hardware acceleration enabled, both audio-only transcodes and full video transcodes eventually stutter after 1–3 minutes of playback.
>> When hardware acceleration is disabled, playback runs smoothly, both for 1080p HW video transcodes and for files requiring only audio transcode.

My setup: Emby Server on Ryzen 5 4600G (AMF-capable), content stored/transcoded from SSD; client Chromecast Gen2, playback via generic Emby App, Mesh Wifi.

This behavior was not present before upgrading to Emby 4.8.x. No similar issues observed on other devices or with acceleration off.

 

Attached 2 Examples :

MovieA = no video trascode required, only Audio is converted = stuttering if HWA is enabled

MovieB = video and audio trascode required = stuttering if HWA is enabled

 

Can you please investigate whether recent changes to AMF handling in v4.8.x are causing unintended GPU involvement in audio tasks, leading to buffer underruns? Is there a fix or workaround planned?

thanks 

MovieA-HWA_Disabled.txt MovieA-HWA_Enabled.txt MovieB-HWA_Disabled.txt MovieB-HWA_Enabled.txt

[averon 7]

same issue and I start getting tired troubleshooting emby every few months over and over by just having emby on auto update. in all fairness, I didnt see any meaningful updates over the last years, besides intro skip, but plenty of bugs. if plex only had not such a bad UI..

Anyway, I am looking forward for a more stable Emby.

Emby Server 4.9.1.1 Beta, as I couldnt roll back to stable without breaking the db.

Not saying this is an Emby issue, as I also use chromecast v3.

Cheers nd sorry for my small rage.

[Luke 42078]

Hi, we're going to have an updated ffmpeg build on the server beta channel in the near future, so stay tuned for that. Thanks.