amp on before radio is on in 96 accord

alright heres the situation..friend of mine has a 96 accord...he has an amplifier with 2 subs running off a stock head unit..apparently circuit city only wired up the remote wire for him...and from what he told me, he says that his subs start making noise before he turns the radio on, and once the radio is on then it stops...i told him they probably tagged the remote wire to accessory rather than the radio/remote turn on wire...thats happened to me before where tagging remote wire to accessory tried to give the subs signal and the subs bounce weird until the radio turns on...he thinks they tagged it at the fusebox...the only other wire i can think they tagged is the radio ignition wire which is white w/ red stripe behind the radio....since its a stock radio, what else could we hook it up to so he doesnt have this noise? like i said before, ive had this problem, but it was with an aftermarket head unit, not a stock so it didnt have a remote wire to connect to.