Crook subwoofer needs replacing and semi understand that increasing to one with higher Watts will not harm the amp , just slightly harder for it to move the cone but will make it harder to kill it, i.e. makes it more robust.
The Unit: TDK S-150 (PC speaker unit system)

System Components 2 speakers, subwoofer
Nominal Output Power 75 Watt
Frequency Response 50 - 20000 Hz
Crossover Frequency 180Hz
Audio Amplifier integrated Magnetic Shield

Patient backside stamped with FSW2040-312 4oHM 20W and see similar speakers but have higher Watts rating. S, is it OK to go slightly higher in the Watts but staying with same Ohms rating, in this case, 4Ohms.
thanks for any helpful advice in advance.
NB I have limited internet so may be slow to repl....

Mahalo