ARRGH Problemo with new rig
 

This has been talked about many times, but this is a different twist on it. AMP HISS! I just purchased an older Bag End d12-d cab and then bought an old Peavey Mark iii xp head to power it. I set it up last night and it was awesome. Absolutely perfect, no hiss, excellent sound ect. Well this afternoon I decided to use a little electronics cleaner on the jacke to just clean it a little as well as the eq slides, now it has thad goddamn hiss when you plug the bass and chord in! Am I missing something here? It didnt do it yesterday and this morning, now it does. Its driving me nuts trying to figure out why. Yes it stops when I palm thr bridge. Thanks for the help

If it stops when you "palm the bridge", my guess would be it's hum rather than hiss. Does it sound like "mmmm" or "ssss"? Very different sounds with very different causes.

more like hiss as in high gain hiss

Static style ssss. probably the usual bad ground nonsense, but it wasnt there yesterday...??? having a hard time troubleshooting it.

Palming the bridge makes me think you have a loose ground wire in your bass. Also, do you have single coil pickups in your bass? That could also be a culprit.

Grounding problems don't cause hiss. Still not sure what the sound you're describing is.

Well im confused. no sound this morning. I thing I must be on a bad electrical path or picking up something in the neighborhood.

Could be. Could also be something in your house running and causing interference. Check your bass and see if it's shielded well.

Florescent lighting can do that. Play in the dark, you'll learn to stop looking.......