Ibanez SRFF805 hiss on active but not passive

I have an SRFF805 that has hiss on the active side of the switch, but not on the passive side of the switch. The hiss is present whether the volume control is full up or full down. Just to re-iterate, it is dead silent on the passive side.

I have another active bass (MTD Kingston Artist) that is perfectly dead quiet. It only has an active circuit. Nothing passive. So, I know my brand new cable and brand new amp are not the problem. It is definitely the SR.

I've seen a few threads in the forums of others who have similar problems, but not much in terms of resolution. One suggestion was to swap the battery. I plan to try that but wanted to solicit other ideas before I pop all the back plates off and start looking around. Someone else mentioned they were going to install some copper shields, but they didn't report back. Would a $1000 SR really need that? I'd expect a bad capacitor or bad resistor, but lack of shielding would imply a pretty serious design flaw.

 

This thread was left behind as the conversation wrapped up in the Portamento thread. The sheilding and all of the electronics are engineered correctly. My problem was a short on the treble pot where it met the circuit board. I almost had it fixed, but got overzealous with the soldering iron and damaged the board. I called Hoshino and they are sending me a new board for $60 inclusive of shipping. This is an awesome bass! I bought mine used off eBay for a great price, so I should have expected an issue or two.