Bluetooth HFP connection error with BC127 module

Hi All,

I am new to BT so hopefully my problem is simple to solve.
I am using a Blue Creation BC127 with Melody v6.0.48 and need to connect 
this to a BT Headset to realise a bedirectional audio comunication
The headset is a BT2.1+EDR unit that supports HFP1.5 and A2DP.
The BC127 supports HFP1.6, A2DP, ...

Problem 1:
- using the open command I can connect with an A2DP profile. (but I need 
the HFP connection)
- Connecting with a HFP ("open xxxxxxx HFP") always tells me "OPEN_ERROR 
HFP"
Is there some possibilitie to check what's the problem here?
I can connect the BT headset to a cellphone without problems

Problem 2:
When sending some commands from the latest manual I receive "ERROR 
0x0012", "ERROR 0x0013", "ERROR 0x001A"
but after searching for a longer time I still can't find a manual that 
describes error codes.

Could somebody give me a hint how to solve my problems?

Regards,
Christian