I am replying just to let you know we are not being rude to a new poster. It's just difficult or impossible to diagnose noises with nothing but written text. If we can't hear it for ourselves, it's difficult to know.
If it were the expansion valve the noise should be coming from the expansion valve. If the noise is coming from the compressor, it's the compressor. Just because it's noisy does not mean it needs to be replaced.
Hope this helps,