Drum out of balance during spin cycles

Hello.

I got a front loading Whirlpool washing machine (8kg ~17lb). It’s about 4 years old.

The issue is that the drum seems to be out of balance during spin cycles. Often the washer is not able to bump the rpm-s up because it’s out of balance. Sometimes I can even hear thumps. The issue starts with a lot less laundry than 8kg. Doesn’t matter if the load is balanced or not.

Could it be worn shock absorbers or maybe something else? The weights are tight and top springs seem to be ok. The machine doesn’t vibrate or make more sound otherwise.

Thanks!