Beko WMA520W and ISE5.

Had the same fault on both of these machines this week but in both cases I could not find a fault and left them on test.
Customers complained of burning rubber smell at end of spin. Both machines about 1yr old, spiders feels ok and drum not rubbing on boot. On closer inspection I find small bits of melted boot rubber on the lip of the drums. This is just the same as you would see on a bearing failure when the drum comes into contact with the boot. Tested both machines on spin with wet washing and found ok????? Does any one have any ideas or come across this before ?
Regards,
Mike.