I have found out that the mic is not working when using Maemo recorder when the n900 is set to silent profile. (record and immediatly play it back --> nothing recorded). In general profile it works. Can anybody confirm this bug? I can't say if it's a Maemo recorder problem or system audio related.

I don't have a structural mic problem (hardware defect) but I did had 3 phonecalls where people couldn't hear me talk. Some other phonecall immediate after this worked fine. Strange stuf.... This must be fixed really soon.