Portable unit very noisy when cooling - can I repair it?

I have a portable aircon unit that work fine - except when it is cooling. When I (assume) the compressor turns on, it sounds like a jackhammer. It’s noisy enough to be heard outside, and far too noisy to be able to sleep. It does cool though, very well.

When the cooling cycle ends, it goes back to the normal sounds.

It’s the middle of summer here and I can’t afford to get a new unit. Is there anything I could do to fix this? Any YouTube videos I should be watching?