I've started using my Ti-Nspire Cas touch again now that school has started, but now when I pick it the batteries are slightly loose and jiggle around a bit, which occasionally causes my calculator to go into a short loop of turning on and off until I take out the keypad and move the batteries around again. Also on occasion buttons on my calculator won't work, such as the control button and my touchpad (both when clicking and moving). Does anyone have any suggestions to fix either of these?