To keep the video working while listening to the iPod you have to select the video source for the ipod inout in the GUI(menu system) Something like menu-source select-iPod-input-video select- TV(or what ever the input is you have used for the TV video input)

Jason
M80 v2
VP160 v3
QS8 v2
PB13 Ultra
Denon 3808
Samsung 85" Q70