[mythtv-users] Up and running, but have some questions/issues

[Joseph A. Caputo]

On Friday 31 October 2003 09:32, James Pifer wrote:
> I have MythTV 0.12 and MythWeb working, running on Redhat 9 on a Dell
> Optiplex 150 (PIII 1Ghz) with 512 RAM. The Tuner is a PVR-350.
>
> I don't have TVOut working so I have it hooked up to my Infocus X1
> using the VGA cable. Sound kind of sucks(headphone jack --->>
> composite A/V), but the video isn't bad. Still working on LIRC too,
> so I'm using the keyboard for control.
>
> Here it goes... Watching a LiveTV and recordings last night I noticed
> a few things.
>
> The commercial skip seemed to be working ok at first, then it started
> to skip too early. It would leave the show 10 or 15 sec early and
> start again near the end of the commercial, with some of the
> commercial still left. Strict Commercial Detection is checked. Maybe
> it shouldn't be?

Well, this is really addressing the symptom more than the problem, but I 
always run with 'Auto Detect Commercials' ON, and 'Auto Skip 
Commercials' turned OFF.  This way the commercials get detected, but it 
only skips when I hit the 'z' key, so I'm guaranteed that it won't skip 
any of part of my show.  Just a suggestion.


> Sound issues:
> The sound and video were out of sync at times. This was mainly when
> watching and recording a show at the same time. These are not checked
> in the setups:
> Aggressive Sound Card buffering
> Experimental A/V Sync
> Extra audio buffering
> Would any of these help that?
>
> Sometimes when I try to start mythfrontend I get an error that
> something using/dev/dsp. If I wait a few minutes or just keep trying,
> it eventually starts. One confusing thing is that the
> "Troubleshooting audio" section says that the instructions don't
> apply to PVR-250/350 and they talk about troubleshooting /dev/dsp.
> I'm using a 350, should I be having this problem?

If you're not using the PVR-350's output capabilities (just for 
recording?), then you're probably still using your onboard sound/PCI 
sound card for audio out, right?  Then you still need to make sure that 
nothing else on your frontend (arts, esd, etc) is opening your sound 
device.

> I think I did see a message about my sound card not supporting Full
> Duplex. I'm running everything on one machine, but since I'm using a
> 350 I still shouldn't have a problem according to the troubleshooting
> doc. Do I have something mis-configured?
>
> According to dmesg I have DMA enabled as well and the hard drive has
> it enabled. (according to "Fast CPU, choppy or jittery video) in the
> troubleshooting.

Right; you don't need to worry about full-duplex if you're recording 
with a PVR-x50.

Basically, all of the problems you described above will probably go away 
if you get yourself set up to use the PVR-350's TV-out & sound out.  No 
more sync problems, and I hear the quality of the TV-out is better than 
anything else; plus, right now you're decoding full-screen MPEG-2 in 
software; that's within the capabilities of a 1GHz P-III, but why push 
your machine that hard when you have a hardware decoder just begging to 
be used?



> Last one is the time. My MythTV box is using NTP for it's time.
> Either my time isn't as accurate as I think, or my cable company
> isn't very diligent on their time. I'm missing the first few seconds
> of the shows I'm recording. Any suggestions on dealing with this?

Most likely your cable provider and/TV network feed likes to start 
things a little early.  Look in Setup->TV Settings->General and enter a 
value for "Time to record before start of show".  I use a value of 180 
(3 minutes), which works pretty well for me.

-JAC