I have some experience with this. I had a single speed mountain bike with a singulator style tensioner and it would pop when climbing. You're right to guess it's the tensioner. Now, I ride an xtracycle with a rohloff hub and use the supplied tensioner. ZERO problems. This tensioner is light years ahead of anything you'll come across. Tension is so tight and machined so well. Expensive, but it will fix your problem.