Hi,
had the exact same problem. wrote to tech support (in germany). they told me that i had to reinstall the BT firmware (they sent me a zip file). but it didn't work for me. always had an error message just after i started the update.
if you want to try if it works for you, here is the installation manual they sent me:
Step 1. Unzip the attached file "ME_F500_F700_F900_BT_Firm.zip".
Step 2. Copy the following 3 files to the root of an empty SD card
- CK5000_290_RLS.bin (929KB)
- flash_p4_lwp.bin (29KB)
- rtl_115200_8192_p4.bi