Without the information requested in my previous response, I can only give you a general answer, but I hope this helps.
The grinding noise may come from either worn out motor brushes or if drain is clogged or the bearings are worn out.
Please try this to solve the issue:
You will have to unplug the appliance and remove the bottom front flap.
Then keep some beach towels and shallow container under the filter.
Now, rotate the drain pump filter anti clockwise to open, clean it completely and make sure it is not clogged.
Also with your fingers check if impellor rotates, then reconnect everything and plug it back.
If the issue appears again, you will have to contact Bosch and check the bearings and carbon brushes for the motor.
I hope this helps, please do not hesitate to ask any follow up questions.
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Have a wonderful day.