Strange delay in audio/video when changing channels?

Not sure if this is normal, but I lost half my cable channels Friday suddenly and traded in my cablecard Saturday morning when Comcast couldn't fix it and found even after trying 2 cable cards that when I change channels, there's like a 2-3 second delay to audio and another 1 second delay to video.

Is this normal? Do others have some wait time beyond 2 seconds to get both audio and video on all channels?

TIVO support thought it was normal, but I never recall see any delay in video following audio.