String changes are my current hurdle. I’ve just started learning a few months ago and so right now I’m working on keeping a good quality intonation after a string change. I think I’ve discovered the issue though. It’s worse for some reason when I go from either the E or D to the A string. And I believe it’s because my bow wants to slide off the ‘good sound point’. So I’m working really hard to get that change corrected in my bow arm.