Another Bluetooth Problem

[VRS73]

Hi All

I have the RNS 510 system in the car. Using Bluetooth my Wife's iPhone 4S can make and receive calls all day long.
My iPhone 5S can receive calls but will not make a call. All I get is three bleeps and nothing else.
Anyone have the same problem? Is it the Bluetooth or the phone? I did ask VW if there was a software update for the Bluetooth system but they have said no.
Its not a major issue, just frustrating as i cannot get it to work.

Any suggestions would be appreciated.

Thanks

Darren