I see your not new to the site but welcome to posting realm LOL.
The pitch could be a few things. Since your only hearing it in the towers its a lot easier then you think to narrow it down.
Its one of these things.
Ground line.
RCA wire
Amp
Speaker
If the amp is grounded right to the battery like it should just make sure the connection is good and solid. Not lose or any sort of bad connection.
Are the RCA for the Tower amp running along the power lines of the amps? If so move them away.
Amp- switch the tower speaker wires to your other amp and give it a listen. You can hook your infinity amp to the cabins. Does this solve the problem in the towers? Does this move the noise to the cabins?
Speakers- if the sound is there even when moved to another amp then your speakers are most likely bad.
If you sound goes away when you plug the towers into another amp then the amp is the culprit check all connections and RCAs
If you checked the above and still have noise, plug cabins into the amp and the noise moves to the cabins then the Amp is suspected of a the problem.
Those are where id start and let us know how it works out for you.
Malo <--- Means--Evil or Mean One. This explains a lot.
2013 Mojo 2.5 Skylon Tower. Bestia < Beast >
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