[mythtv-users] A poor HD viewing experience

[Tom Lichti]

Jesse Dhillon wrote:
> Hi,
> 
> I have the Air2PC 5000 HDTV tuner installed in my myth machine, and I 
> can use it to get some local HD channels via QAM. The problem is, 
> though, when the box tries to play the video, it is ridiculously choppy 
> (half-second pauses every 1-3 seconds). Even if you have the patience to 
> watch this for 5 or 10 minutes, it does not clear up, and the disk is 
> thrashing the entire time (which I guess is understandable since it's 
> buffering).
> 
> CPU usage jumps to around 50% for Xorg and 50% for mythfrontend. I'm 
> guessing this is not the intended behavior (the choppiness), but I'm at 
> a loss for how to troubleshoot it. Here are my specs:
> 
> Athlon64 3200+
> 1GB RAM
> Ubuntu 6.10 (Edgy, upgraded from Dapper)
> MythTV 0.20 packages from Ubuntu repo
> 500GB SATA HDD (Holds OS, videos right now)
> 250GB SATA HDD (Holds nothing right now)
> 2 Air2PC 5000 tuners
> nVidia 6800gt 512MB
> 
> So I'm pretty sure this machine should be able to handle this. If anyone 
> has an idea as to what's useful information in this case, and how to get 
> it, I would be grateful.
> 
> Also to note, I am not running a window manager. In ~mythtv/.xsession I 
> run mythfrontend directly, and this could be a problem. I'm currently 
> looking into how to setup a compositing window manager, or something 
> like aiglx. I tried xgl+compiz, but alas, no xv meant crashes when I 
> tried to play video.

I definitely think that is the problem. Have you/did you try the NVidia 
binary driver? I can't see why it wouldn't work for you.

Tom