[Voyager]

Hi all -

I'm looking for some feedback from AMD Fusion (E350 - E450) owners who are using the pre-Frodo nightlies (since Audio Engine) with WASAPI audio output.

Here's the issue. I've been searching like mad and still no solution...
My audio is connected via optical SPDIF to a DD/DTS 5.1 receiver. I use WASAPI.
My TV is a Panasonic HDTV capable of 23/24/50/59/60 Hz, up to 1080p.
I'm using true full screen, auto change refresh, sync playback to display, DXVA rendering, hardware decoding enabled...

When my TV is at 50 Hz and I play 25fps PAL video (typically progressive DVD or a European Bluray rip at 25fps - yes they exist but are rare), I'm getting heavy stutters, I notice a lot of missed vblanks and I see the fps rate "dancing" around 25, but it's not steady.
The log is filled with discontinuity errors.

I tried with deactivating all Video quality enhancements in CCC. Nothing made a change.

Then I found a number of ways to get around it and get smooth video:
1. using DirectSound instead of WASAPI
2. forcing deinterlacing (to fps = 50) and everything stabilizes at 50fps
3. prior to launching XBMC, I open CCC, apply the xbmc preset and leave it open(!). Then launch XBMC, everything works perfect. From the moment I close CCC, XBMC does stutter again in the above situation.

Especially the latter, I don't understand. That is also why I had some trouble identifying the right setting in CCC, simply because whatever I tried made it work, but only for as long as I left CCC open. I found that actually having it open solves the issue, but as soon as you close CCC, the issues come back.

Any thoughts or ideas?

regards, Voyager-xbmc

[DDDamian]

A couple: if you're going to use Sync to Display with a passthrough format you're asking for problems. Sync to Display will need to either drop/duplicate packets or resample the audio. The latter is impossible without decoding the passthrough format, the former is likely to disrupt encoded audio.

Switching to DirectSound essentially forces decoding which is why it helps, but be aware you'll be getting decoded audio is most cases.

[Voyager]

hi Damian - I'm using the Audio clock to sync video. The reason is indeed I don't want any drop/dupe or resampling. I tried without sync to display, it's just marginally better, fps is still dancing up and down. The real difference is with the Catalyst app being open...

And regarding the decoding, I'm just bitstreaming AC3 or DTS. I don't have any of the HD variants in my library :-)

[DDDamian]

hi Damian - I'm using the Audio clock to sync video. The reason is indeed I don't want any drop/dupe or resampling. I tried without sync to display, it's just marginally better, fps is still dancing up and down. The real difference is with the Catalyst app being open...

And regarding the decoding, I'm just bitstreaming AC3 or DTS. I don't have any of the HD variants in my library :-)

That is starting to sound more like a CCC issue then. Ok glad you're clear on the Sync to Display options - just wanted you to be aware of what was going on behind the scenes there.

It may not show me much but if you post a log I'll take a look

[Voyager]

short update - the solution has been found, and is here: https://github.com/xbmc/xbmc/pull/1352

[DDDamian]

Great job Voyager