My trusty Digitech QM1323 multimeter hasn’t been so reliable recently. It has been flaky with its readings, and I thought it might be faulty connections where the leads plug into the multimeter. Resistance and voltage readings seemed like they only worked sometimes, and I was always pushing or turning the leads where they plugged in.
Turns out it was very simple to fix once I opened it up. The main lead terminals had snapped off from the board, not enough solder on them. I flowed plenty of solder on the joints, held in the right spot, and now my multimeter is working perfectly.