Music plays fine over bluetooth but when I phone anyone it soulds like Dr Who's arch nemesis

You might want to give us your background / your car / what your MIB system is etc etc. What you describe could be numerous things.

17 hours ago, rit said:

Music plays fine over bluetooth but when I phone anyone it soulds like Dr Who's arch nemesis

If music over Bluetooth is fine then the Bluetooth and the MIB are probably OK, so this sounds like a phone or mobile network issue?

7 hours ago, PetrolDave said:

If music over Bluetooth is fine then the Bluetooth and the MIB are probably OK, so this sounds like a phone or mobile network issue?

I totally agree, good music means the connection is ok.

How is the quality when you use your phone without the bt?

Its a possibility that the AVRCP protocol is struggling here a little. I would personally do two things:

1) Make sure your MIB system is running on the latest available firmware (other postings can help you with that)

2) Lock down your AVRCP version to something like 1.3 or 1.4 - you have to enable this in Developer mode on your Android handset (latest is version 1.6).

Thanks guys - Changed the AVRCP to 1.4 and it started working again. Strange thing is I changed it back to 1.6 version and it continued working

That will because the MIB system does have issues sometimes with negociation. Hard locking down only presents one protocol. Lock it to 1.6 if it works for you.