My rear wheel is making a weird noise which at first I thought was the wheel bearing but after constantly having been told by mechanics that there is no play on my wheel bearing and it's fine, I just checked my rear wheel and upon spinning it, it's making a "tish tish tish" sound when it spins around.

What could it be? I think the back rotors might be warped causing this? I only checked one side, I'm about to go check the 2nd side to see if it's the same noise on the other side rear too.

 

The other side doesn't turn as easily as the tish tish tish side (left) the (right) side feels like it's very mildly applying brakes and pads rubbing against the rotor. The left side goes "tish tish tish" (sound it out)... and the right side has a consistent "tish" sound to it, sort of like a sanding paper sound.