I've had my Fold 4 for 2 months. When I first got it, it was connecting to my car stereo for calls, contacts and audio. Shortly there after the 3 sliders were appearing however I was unable to move the audio slider to blue. Now the audio slider doesn't even appear. I only see calls and contacts now.
I've tried several things. One suggestion was to clear my bluetooth cache however when I get to that point both clear data and clear cache are greyed out and cannot be selected.
On a side note; only one month after purchasing, my fold large screen already has a 1 -1/2" black strip on either side of the fold. Really disappointing performance for the price.