Posted for Don Morris <n23sw@cableone.net>:

 During the time I owned my 360 I bought some new ANR headsets.  Using  the
new Lightspeed headsets I got feedback every time I transmitted.   Called
Lightspeed.  They told me some headset cords are not insulated  well enough
and cause feedback in composite airplanes.  Changed to  David Clarks.  They
worked fine with no feedback during radio calls.
 
 Don morris