Hello, I have been playing double bass for three years and use it as my second study at University. I also suffer from elements of HyperMobility Syndrome, meaning that I regularly pop out joints. A few months ago, I dislocated my left thumb so took a break from the bass for a while. Since I've started playing again, I have noticed that my left arm gets really painful in the upper muscle, almost like I physically can't hold my left arm up anymore. I'm not aware of gripping the neck more than I should be but I wondered if anyone had any ideas of what I could do to help improve the pain? I've tried lowering my bass so that my arm isn't as high. I've also spoken to my teacher who wasn't sure what to suggest. I would be grateful for any help from anyone Thank you.