[TriLUG] Troubleshooting dropped frames with firewire and dvgrab

[T. Bryan]

So, I finally bout a firewire card for my main Linux machine.  I'd like to 
download the video from my camcorder and burn some DVDs.  I've done some 
reading, so I have a pretty good idea of the process, but I'm running into a 
problem with dropped frames.  

After trying to download the video, I see messages like this 
in /var/log/messages
Aug 20 10:49:48 localhost kernel: dv1394: dropped a frame during reception
Aug 20 10:50:04 localhost kernel: dv1394: dropped a frame during reception
Aug 20 10:52:09 localhost kernel: dv1394: dropped a frame during reception
Aug 20 10:52:56 localhost last message repeated 3 times

When playing back the video in Kino, I get messages like this in certain spots 
of the playback.
AC EOB marker is absent pos=64
AC EOB marker is absent pos=66
AC EOB marker is absent pos=64
AC EOB marker is absent pos=66
AC EOB marker is absent pos=64
AC EOB marker is absent pos=65

In Kino (and in Xine if I export the video to MPEG), I get strange video and 
audio problems around the spots where I'm seeing those EOB marker messages.  
The video gets jumpy, and there are often some scratchy sounds in the audio.  
Sometimes it's just a few frames.  Other times, it persists for a few 
minutes.

My machine is older, but it's not ancient.
AMD Athlon 1 GHz
768 MB RAM
Drives:
The video is being stored to /dev/hda.
/dev/hda 160 GB IDE, dmesg says UDMA(100)
/dev/hdc 8 GB IDE, dmesg says UDMA(33)
/dev/hde 120 GB IDE, dmesg says UDMA(100)
/dev/hdg 120 GB IDE, dmesg says UDMA(100)

I'm using dvgrab through Kino to get the video.  (I also tried dvgrab a couple 
of times without kino, same result.)

I'm thinking that all of my problems are probably related to the droped frames 
during download, but I'm not sure what to try next.  The only thing I've seen 
is to verify that DMA is enabled for the drives.  (I think it is, but I'm not 
sure how to check.)  I'm not putting any unusual load on my system during the 
download.  

I think that this machine *should* be able to grab the video without trouble.  
One of the things I found online even mentioned one of the developers using a 
K6-2 333 MHz to test capture on a slower machine.  I'm not sure what to try 
next other than starting to swap out lots of parts on my machine.  That would 
be fine, but I hadn't really planned on upgrading.  :)

Has anyone done any troubleshooting for this type of problems?  Any ideas?  

---Tom