Metronome is ruined and Instrument is playing when you don't select anything

I have found two very annoying issues in MS 4.5
The first is, if you activate the metronome and hit play, it will start playing as usual, but if you enter some notes, in this case I was working on a piano arrangement, it plays an off time piano sound along with the metronome sound, which is really annoying. Where is this piano sound coming from? I've tracked it to the metronome channel in the mixer cause that's where is coming from. How? I don't know! this is weird and annoying.

Second issue:
When you get out of the editing mode, (When you click outside the score, selecting nothing) if you play your MIDI keyboard, you will be playing the last instrument even if there's nothing selected! this is so annoying and I can't focus on my work, I can't be taking my headphones on and off. This was something it never happened in Musescore 4.4, where if you didn't select anything, even if you played your MIDI keyboard, not any instrument would be playing.

Need a solution for this cause I can't downgrade my version unfortunately