My IPhone Pro Max 13 doesn’t pick up left and right separating of sound when operating through plugged in headphones. But the two channels were working great before!

It almost seems like a case of Apple enabled sabotage . For how else does perfectly calibrated stereo sound signals going through BOTH SIDES of my headphones while frequently listening to online audio… suddenly turn into a boring,slightly-less-audible MONO experience! It’s definitely not the headphones that are the issue,since they didn’t happen to come with any adjustable knobs.