[DSTAR_DIGITAL] IC-E92D RF feedback

[clayro]

Hi, has anybody had any problems of RF feedback when using the external hand 
microphone plugged into the top socket?
When using the radio on 430 mhz band at 5 watts, there are lots of beeps coming 
from the speaker/mic and the TX audio is broken up,this does not happen at 
lower power levels.Any ideas?
Bob G8SDU