This is a known “issue”, since you are using recently released software on older hardware.
Besides trying to downgrade to a 3.3 version as you had before, the actual solution would be to change the USB hub for one that’s supported. I do not think you will have issues other than that annoying message and not being able to use Apple Car Play, but playback and Android Auto should work ok.
You can get further information here → USB hubs are not supported. Please remove