Bluetooth issues in car

Hello everyone, I am borrowing a oneplus 2 from a friend while my phone is in for repair, I have had it for about 12 hours now and have found an issue with the Bluetooth, when connected to my car (its a JVC aftermarket stereo) it loses connection every 30 seconds. I have tested the JVC with my girlfriends Sony xperia m2 aqua and it works flawlessly, has anyone else had this issue?? And if so, how did you fix this?
Thanks