Subtitle problems with hardware transcoding still unresolved (?) QNAP , Emby 4.8.11

[BlueberryOats 0]

I'm on a QNAP 464 and Emby 4.8.11 most things work great thanks devs Emby is awesome, however:

If I enable hardware transcoding, some PGSSUBS will be rendered outside of visible video frame. You can sometimes see the tops of letters just at the bottom of frame, so they are are indeed rendered, but outside of the video frame. This problem vanishes and everything is OK immediately when hardware transcoding is disabled.

(also enabling the option "on-the fly extraction" seems to pretty much break at least SRT subs entirely, they go completely out of sync and can't be manually synced)

The problem is at least reproducible on iOS, Apple TV and Edge browser on PC so it seems device independent. I can also test Android TV on Nvidia Shield if needed.

Suggestions?

 

Edited September 22, 2025 by BlueberryOats

[Luke 42077]

 

Hi there, let's look at an example. Please attach the information requested in how to report a media playback issue. Thanks!

 

[BlueberryOats 0]

Took a while but I've now updated to latest everything, on Emby 4.9.1.90 now and no improvement. QNAP 464.

Software transcoding is all ok but the moment I enable hardware transcoding, PGSSUBS are rendered outside of visible frame, sometimes with top of subtitle visible at very bottom of frame. Here's logs attached. 

embyserver-63899689960.txt ffmpeg-transcode-a8bcf689-800b-46ff-b336-e14c308f0917_1.txt hardware_detection-63899690043.txt

[Luke 42077]

OK we are looking into this. Thanks.