I posted this on the DVBViewer forums a while ago, and haven't had any response there. I figure there are some bright people here who might be able to help.
In newer versions of DVBViewer (including the latest v4.2.1), what essentially happens is that if the DVBViewer window is not run in full-screen mode, the video becomes quite "jumpy" - every 5 seconds or so the video will freeze for about 1 second, before resuming. It's very distracting and almost looks like it's dropping frames - although the audio is fine. If I play it in full screen mode, the video is smooth and works fine - the symptoms only occur when DVBViewer is in "windowed" mode. I am using EVR rendering mode (running on Vista Business edition) with the Cyberlink codecs for H.264, as I have a graphics card capable of hardware decoding.
Version 3.9.4 works perfectly, but is quite old. I tried the beta of 4.0 earlier this year, and it had some problems with the video being quite "jumpy". I assumed this was just a bug in the beta, so waited till the final version of 4.0 came out, and installed that. The same problem occurred, so I reverted to 3.9.4. I have tried installing the latest version (4.2.1) and the problem still exists - so yet again I have reverted back to 3.9.4.
Does anyone have any suggestions as to what the problem might be, and how to fix it?