Can anyone help told a few times now that when using my bluetooth handsfree the callers are struggling to hear me,i can hear them fine but callers can't hear me clearly ! I have fitted a stubby & wonder if that affects the signal ?
If you can hear them clearly and they can't hear you, I'd suggest it's more likely a problem with your microphone, rather than the aerial (since you're receiving a clear transmission one way).
Have you got the microphone on top of the column? I'd expect so based upon it being a coupe and thus later year, but BMW switched locations from near the rear view mirror and used a better mike to improve things.
Mine works just fine with Stubby, so don't see that as an issue. Not sure it even uses that aerial