Just an update on this: I noticed what my problem was eventually.<br><br>My (rather simplistic) assumption that since VDPAU was working in XBMC that it would also work in MythTV turned out to be wrong.<br><br>XBMC 9.11 was happy with the VDPAU version I had installed, *but* this was the default version 185 which came with Ubuntu 9.10<br>
<br>The Myth 0.23 fixes branch required libvdpau > 0.2, which does not come by default in Ubuntu 9.10.<br>So while you could select VDPAU in the Playback settings, it paid no attention to you. CPU usage for HD decoding was > 1 core worth on my Atom machine, and although that did appear to leave CPU headroom left over, Myth didn't like it and we got the prebuffering pauses.<br>
<br>In fairness to it, it did warn me gently about this VDPAU business when I ran ./configure before building ... but I did not notice.<br><br>So this was a good excuse to upgrade to Ubuntu 10.04 LTS.<br><br>So the sequence:<br>
<br>* upgrade to 10.04<br>* $sudo apt-get remove pulseaudio<br>(pulseaudio caused all manner of audio troubles for me on 10.04)<br>* svn up on the 0.23 fixes branch, just in case<br>* make clean<br>* ./configure<br>* make<br>
* sudo make install<br>* and turn on additional audio buffering in Settings ...<br><br>.. and all was well<br><br>I now have perfect HD playback using "VDPAU Normal" for playback. And DVB-T as well!<br>Happy days.<br>
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