CarPlay Volume Locked

So, in early April. 2024, I noticed that my Apple CarPlay volume was intermittently locking at the last volume setting, and I could not adjust it in my car. This is with any app that plays audio. Note: when I switch to the car’s radio, there’s no problem with the volume.

It has been getting progressively worse, and now, the volume is locked at a high volume I set several weeks ago, and there is no way to adjust it. I tried reinstalling CapPlay and doing several other “fixes” suggested online, but nothing has worked.