Problem solved.

Got an Exile X300.2 for £80 ex-demo from a friend that runs a car audio store and then some meathead jumped on the roof of my car Saturday night which looks like it will be an insurance write off.

The system was de-installed from one car and has sat in the new car disconneted for a while because I know this amp has a problem, the cabling is all fine (I've visually inspected it since taking it out of the old car) plus if it was shorting on the firewall to cause this problem, the other Sapphire...

Not yet to be fair. The system has been sat in the car disconnected for ages, but I'm of a mind to resurrect it if the amp issue can be solved.

That's what's confusing me, the whole thing looks pristine inside. No toasted components, nothing.

Definitely no cross connection, all the wiring has been done with insulated crimp connections.

Hi guys, hoping you can give me some help here; I have a pair of Sapphire 3.0x amps that have been giving sterling service for years, but one of them draws around 300mA when it's off (standby) which obviously kills my car battery! Any ideas what the problem may be? I have a fair level of electronics...