I replaced my 48/3000 with a 48/5000 recently.
The new 48/5000 makes a howling noise once the fan starts.
I have the feeling the chassis acts as a kind of pipe/flute. If I press my finger against the chassis the noise stops. If I e.g. press some plastic stuff (2cm x 2cm) against the chassis it stops as well.
The MP is mounted on the normal installation kit on a stone wall. Also the two bottom screws have been used to fix it completely.
To be honest the howling noise is sometimes really getting on my nerves.
Any similar experience? Any solution?