I have a 2018 S90 T6, had some a/c issues last year, got them fixed. Recently, I started to notice that when I pull my seatbelt out (no matter the temp outside) the strap is really hot. I live in Houston, TX, so I'm no stranger to hot seatbelts, but this is over the top hot. It feels like someone was holding a heat lamp to it. This happens at starting and if I'm in a parking lot for a little bit with the seatbelt off, once I pull it back on, it's back to being hot. Again, with the car on and cooling the whole time.

So, then I sat back there and turned the a/c on, the air blew out hot, too. Front a/c is ok.

Firestone won't touch it, and I don't want to pay dealership prices before I check all my options. Any thoughts?