Hi,
I suspect this is caused by a combination of BOTH the 950 and the digital source. It seems the 950 can tolerate a short break (1/4 to 1/2 second) in the digital data stream, and then continue decoding when it reappears. However, if the break is longer than this, it sees the digital data stream when it comes back as a "new" signal, and has to go through it's recognition and synching routine before it allows audio out. This is where the 2-3 second delay comes in (and if the source has a longer break, that time will be added to the 950's 2-3 seconds). So if the new HD DVR can switch channels and keep the data break under the 950's threshold, there will be no delay in the audio, the old box must go over the threshold, and then gets the 2-3 second delay as well as any additional delay from the box.

HTH,
Peter