re:SR22 G1 manufactured 2004 strange noise/ monotonous squeal while in flight/taxing
It happens with no regular pattern, on cruise, approach, taxing. We have tried to isolate the noise and apparently it does not come from any avionic/electric/electronic equipment. We believe it might be air stream induced. Our local cirrus maintenance facility (Berlin) could not come up with a remedy.
An Cirrus-experienced A&P should check the door seals carefully. A sealing problem could change with different windstream speeds and direction, but normally it would not be heard while taxiing.