After replacing my worn-out Magura brake pads (MT4 brakes, 7P brake pads), I now have a continous light friction noise when the wheel is spinning (front wheel).
The brake disc is brand new as well. The former one was slightly bent by a couple mm. I noticed the pistons are not fully back in their original positions.
I've tried to fix that by pushing the pistons back in their original position, removing a few drops of brake oil, tried also applying Magura's instructions to "re-mobilize" the pistons, all to no avail: the issue keeps on coming back as soon as I hit the brake lever. The friction noise is back with the piston again not returning to their original positions.
I am totally clueless regarding further steps to resolve the noise and piston return issues. Any advise would be very welcome.