Static Charge / Avionics Squeal

[Runtoeat]

AOPA recently had a short article about static electricity buildup and the various ways to eliminate it. The article said if one ever experiences "motorboating" or a "squealing" noise in their radios, this may be attributable to a static buildup. I've had two occasions where I have experienced a squeal in my avionics which rendered my radio unusable. The first time this occured, I was on the ramp doing my runup. Shutting down the engine and avionics and restarting the engine eliminated this problem. Recently, I experienced the squeal while in the air. I belive that my passenger shut down my Garmin 495 GPS and rebooted it and stopped tha squeal but am not sure if he may have also shut off my radio and then back on too? I took care of flying chores while this was happeniing and wasn't able to reconstruct the order of events afterwards. Any thoughts on this would be welcomed

[Tom Baker]

^{I've seen a bad ground or poor connection on the intercom do this.}

[Runtoeat]

Thanks Tom. I'll check those connections.