Harman Kardon iSub

[Christian Kotz]

Hi All
Anyone know who would be responsible for repairing Harman Kardon 
iSub's, the USB Mac specific versions. I'd imagine it would be the same 
people who fix JBL Creatures and HK Soundsticks. I'm just wondering as 
my iSub has developed an unusual 'buzz' like the sound electronic 
interference/noise that continues when computer is off. Only way to 
silence it is to mute the computer while it's on.
Any ideas?
Regards Christian