When I was using my mp20, sometimes would hear some vibrations and weird noises. Realised eventually tt the wet and dry side are not aligned properly. Then after some exploring, realised that over time, the wavemaker was slipping downwards. Tt's why the instruction manual stated to clean both the wet side and dry side of the tank before mounting the wavemaker.
Not sure if it helps, but if you can't solve the problem, best to bring it back to Victor as it's still under warranty.