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Smooth streaming audio sync issue on WP8

Topics: Windows Phone 8
Dec 10, 2012 at 6:57 AM

Hi all,

I'm having issues with both SMF *and* Player Framework just released on WP8, in that any SS video I play (even the ones in the samples, like big buck bunny - the audio is out of sync (by a fair amount). 

Mostly happens on device (Nokia Lumia 920). SMF same videos are fine on WP7 (and our streams are used on XBOX and Windows 8 without any issues). 

Just download the PF source, fire up the WP8 version, run up the sample and off it goes.

Seems the only common component is the Smooth Streaming Client, which I've double checked is the correct version.

Has anyone else had this issue?



Dec 10, 2012 at 7:16 AM

Oh - another thing... If I run a progressive fast pre-roll ad, the ad plays fine (and in sync), but the video is lucky if it gets one frame per 10 seconds... serious stuttering. Frame rate without ad seems fine (other than sync issues). 



Dec 10, 2012 at 9:11 AM

Update: Playing media with SmoothStreamingMediaElement directly also leads to sync issues, although not as often with BBB. Our streams the problem is rather more apparent.

Dec 10, 2012 at 6:00 PM

Hi Jordan, I am unable to reproduce this with the sample and the Lumia 920 (as well as the emulator). The second issue you're reporting about the poor FPS sounds similar to issues I had when testing on pre-release WP8 hardware and software; are you testing with retail hardware?

Dec 10, 2012 at 11:10 PM

Hi Tim,

Unfortunately it happens on device (a number of them) and in the emulator. 

I may have to try and email you a stream to test with. Unfortunately they are geoblocked to inside Australia and would need to get Akamai to allow your IP.

As i said, BBB the problem is not as apparent (sometimes it is out of sync, other times its fine). Our streams it is very apparent. 



Dec 13, 2012 at 12:27 AM

Hi Tim,

Is there some way I can get you test stream so you can replicate the issue? I'm sure we're not the first and last to have the issue.

We're a major public broadcaster in Australia with apps on XBOX and Windows 8, and we're being held back by the sync issue on WP8 (we may deploy WP7 this week). 



Dec 13, 2012 at 8:49 PM

Hi Jordan, yes, I'd be happy to take a look at your stream and escalate to the smooth streaming team if necessary. Please contact me directly (click on my name via CodePlex to send a message) to provide more info.

Thanks, Tim

May 16, 2013 at 10:01 PM
Hey folks, I'm running into this same problem (might not be the same, but the result is ... audio sync issue on WP8 device and emulator)

I have my sample stream though, if that helps:
May 17, 2013 at 12:23 AM
Hi All,

The problem was that the streams were encoded with WMV and not MP4. We switch our entire encoding process across (thousands of videos!) and it worked. Apologies for not updating the thread.


May 17, 2013 at 12:26 AM
That shouldn't be required though, VC-1 (WMV) Smooth Streaming is supported as far as I know. Changing our encoding to all H264 seems like a terrible solution to this problem.
May 17, 2013 at 1:02 AM
Unfortunately pragmatism won the day. VC1 works fine on everything by WP8. The player stack (or maybe the player framework) doesn't support hardware decoding of WMV.