#1
I have a very nice electric acoustic guitar which has its own pre-amp - but whenever i actually plug it into an amp, if I stop muting the strings with my hand, the amp gives me masses of feedback. Any ideas what could be causing this?
#3
Most semis and acoustics do that

try facing the amp the opposite way and sit/stand as far away from the amp as possible
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#4
^ Those would help. Often, guitarists put something over their soundhole in live situations. You could try that also.
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