I Pod and cube

[Richard Clark]

I have noticed when my ipod is hooked up to my cube and i am listening 
to music with I tunes while updating  Ipod the Usb ports cut in and out 
which i can hear with the speakers that fade in and out and also with 
my external cd-rw. Looks to me that it is a power problem my cube is a 
stock 450 and i was thinking to upgrade the video card, hard drive and 
eventually also the processor but have reserves because if i have power 
problems now i'd hate to see with the upgrades.
any ideas or comments from the professionals out there?