The 'old' file contained an rSAP session, the other file probably contains audio, that's why it's so huge...
It looks like there is a problem in the Bluetooth handling. The WireShark tool shows that the phone sends 'malformed packets', then the car aborts the connection. So maybe my app does better because it doesn't use the Bluetooth stuff of Samsung rSAP, but that's guessing. It's also strange that changing the SIM card influences Bluetooth, but in software everything is possible
You have to decide if you want to give my app a try - it needs root access. Rooting or installing my app will not delete any data, but you'll lose warranty and there is a (very small) chance that something goes wrong while rooting.
Another possibility is to get a new SIM card from the provider. You should try to get a different
card, from a different batch and/or manufacturer. Of course, if your current card is not very old, chances are high that a new card has the same problem. But it's worth a try.