I think i have to agree with that - Bluetooth streaming audio and wifi on - causes problems -
For me i seemed to notice it more when I am on the edge of my wifi signal - so i attributed it to the phone trying to reconnect.
FWIW, I solved my skipping/dropout problems when streaming audio over BT by using the Tasker app from the Market to change my default clock settings whenever BT is active. I set to 400 min - 768 max & On Demand, when BT is active and don't have any problems.