This is an occupational hazzard of playing the fiddle - that is, going deaf in the left ear. Some fiddlers develop this problem after playing for many years. So some sort of an ear plug might be a good thing.

Then you mention playing with the fiddle against your arm or chest as many old-time fiddlers do. That's not a good idea, since you are holding the fiddle with your left hand and in the process, bending the wrist back which can lead to carpal tunnel syndrome and other wrist problems. You should be able to hold the fiddle with your chin, and a shoulder rest if need be, without using your hand. Proper posture is very important, so your wrist does not take on the whole weight load of the fiddle. I know, because I'm recovering from some wrist problems, and I've tried to hold the fiddle in a proper manner. But there's a lot of repetitive motion going on with the fingers and the muscles can be over stressed without proper attention.

As to strings, try some perlon core strings such as Thomastik Dominants or Infields. They're a little softer sounding.

Cheers, S. in Seattle