| MiniBil,
I'm not 100% sure that the HiFonics has a built-in remote turn on lead--I can't seem to find any details on the web that says it does.
I'm surprised the shop didn't rig a custom relay from the stock headunit--the stock head does have a power/antenna lead you can tap for remote turn on.
an aftermarket unit will not necessarily remove the whine you're hearing since it might be interference at the amp down. but it will offer considerably better source quality to the amp. Not sure if you know but the stock head unit actually amplifies the signal before sending it to the speaker. so
inside the stock head the signal gets amplified once -> then sent to the speaker output -> you pick it up there take it to your amp and convert it down for the amp -> the amp then amplifies it back up to send to the speakers
there's a lot going on, and of course this ignores the fact that the actual signal from the stock head isn't near the quaility of a preamp output from a mediocre aftermarket unit.
check out davebrets guide to see how you can maintain the steering wheel controls.  | 
