[mythtv-users] XvMC channel change freezes front-end

[sglynn at urban.net.au]

Hi,

I'm running KnoppMyth R4V5 (MythTV .16) on the following hardware
Compaq EN SFF P3 730MHz
Intel 815 on-board Sound, Video, Network
160GB HDD
256MB RAM
Avermedia DVB-T 771
GeForce MX4000 TV-out
Kernel 2.6.10-rc2 (for Avermedia frontend MT352 module)
Combined frontend backend box

Unfortunately the KnoppMyth community can't suggest a remedy to this one, so thought I'd pass it onto the wider Myth users community.

Because my TV card is DVB, the system is easily handling streaming this to and from disk (backend uses less than 10% CPU). 

Without XvMC, the system isn't powerful enough to playback the 720x576x25 MPEG2 stream, without needing to pause for pre-buffering every few seconds. With XvMC, it has about 25% idle CPU, so easily does the job.

However, when I change channel under XvMC, the pre-buffering takes place, then the OSD and moving image pop up and then a second or so later when the OSD begins to fade, the front-end freezes and leaves an image on screen. The front-end becomes unresponsive (as far as display goes). It is still processing keypresses, as the aspect change (W) changes the screen boundaries, though doesn't resize the frozen image. Esc doesn't take you back to the myth menu either. A killall is required and then once restarted it comes back to life.

Is this a general XvMC issue that everyone has and has yet to be resolved, or am I part of a select few here, and if so does anyone know how to resolve? If further info is required, please let me know, I'll be happy to provide.

Regards
Simon