Iv not seen anywhere which states which unit works fully with the different stereos i just read that the 5K pn had worked for someone with a swing stereo. How do you know that the 3C8 pn works with the swing - have you got one?

Try to change BT AVRCP version on your phone before trying to switch BT module

This did the trick on my Ocatvia III while using an Android 11 phone