There are multiple, lengthy, recent threads about this.
tl;dr There is a recent iOS update that (14.6) that addresses the volume issue and has resolved it for some (not all people.)
There is a iOS beta (14.7 and 15.0) that addresses other CarPlay issues.
If you are running the latest iOS and the latest Sync and still have issues, file a bug report with Apple. They are working actively on these problems.
File a complaint with Ford as well, as Ford (Sync) updates also continually break the integration.
Neither of them are reading forums.
Also, it seems YMMV depending on what model iPhone you have. Those with an iPhone 12 *seem to be* experiencing fewer issues than those with iPhone 11. (But iPhone 12 is not a silver bullet.)
tl;dr There is a recent iOS update that (14.6) that addresses the volume issue and has resolved it for some (not all people.)
There is a iOS beta (14.7 and 15.0) that addresses other CarPlay issues.
If you are running the latest iOS and the latest Sync and still have issues, file a bug report with Apple. They are working actively on these problems.
File a complaint with Ford as well, as Ford (Sync) updates also continually break the integration.
Neither of them are reading forums.
Also, it seems YMMV depending on what model iPhone you have. Those with an iPhone 12 *seem to be* experiencing fewer issues than those with iPhone 11. (But iPhone 12 is not a silver bullet.)