Mercedes-Benz: Help: Noisy cabin temperature sensor blower

1989 124 250D, signalrot

My cabin temperature sensor blower - the one sucking cabin air into a
sensor under the glove compartment is noisy (especially when it's hot
outside), sounding like a CPU fan being out of balance.

Should I replace it (easy) or is there a good trick around to make it
silent again?

Thanks in advance,
Christian from Denmark