Devo 7E Strange Trim Behaviour (Constant beeps!)

Hi All,

This morning I've turned on my 7e after a few months break (2x3 and 4-in-1 modded) and the poor thing is going crazy! Here's what's happening:

1) Turn on the transmitter, it boots and beeps as if I'm holding a trim up / down button
2) I thought it may be a short on the extra wiring for the 2x3 mod, so opened it up and removed everything.
3) Switched it back on, and it's still doing the same beeps with the AIL and THR trims moving up
4) If I press the opposite side of the trims... beeping stops.
5) Strip it down, check the trim boards (two micro switches each for shorts) - All looks good with the meter reporting open circuits as expeced)
6) If I start the transmitter with the affected trim boards disconnected, all works happily.
7) Re-connect the trim boards, and the beeping / ghost signal is back....
Check for the fourth time that there's no shorts, nothing!
9) Check voltage on the lines, and I'm only seeing ~1.4V would have thought this should be 3.3?
10) The issue goes away if I gently touch the exposed areas of the trim boards, almost as if something's floating.. or the trim boards are acting as an antenna and picking up an induced current interference?
11) Next step is to disconnect the 4-in-1 and see if it's causing an issue?

Has anyone seen anything like this, have any ideas to how I can go about troubleshooting, or is it time to replace the 7e?

Cheers,
Nathan