Is it me?
I have a Bosch PEX400 which is a couple of years old. Disc attachment is by loop and pile (Velcro type). In use, the thing works well for a few minutes and then throws its disc off. It will then not re-attach reliably, suggesting that the loop pile is no more. A new disc restores it to health for another couple of minutes. Altering the rotation speed appears to have no effect on when the disc becomes an UFO. Holes are carefully lined up each time with the base. Deliberately obstructing the holes make no difference though.
I consider this to be a fault as it happens regardless of disc brand, including Bosch, so I bought a new sander last week. It was a B&Q own brand Mac Allister, bought as a cheapy because my Bosch is in France. Spec is dual base 150 and 125mm, variable speed random orbit.
This one shows exactly the same symptoms. Disc nowhere near worn and becomes useless.
So is it me, or is this to be expected?