Audio volume – small bug?

Hello, every now and then I could observe the following phenomenon (or hear it…): After driving off, the radio is sometimes too quiet. The up-tuning of the volume via the + button on the steering wheel changes almost nothing, although the length of the corresponding bar changes on the screen. The puzzle solution: The displayed bar is not the one for the radio (i.e. “audio”, but for “language”. If you then use the voice control “radio louder” or similar. The radio not only gets louder according to your wishes, but you can influence its volume again from the steering wheel. Why the “language” is mogging in between when using the steering wheel and then you have to activate “audio” by means of the voice control has not yet opened up to me. And also the question, whether you can solve the small problem differently (and possibly even permanently), I can unfortunately not answer. But it is also only a small B ug (or a fault in operation?)… Nice greeting