If your in-game settings are at max you can always increase the overall volume of your sound-card ( access the program via Control Panel ).
That might bring your gramophone volume up to an acceptable level but risks making all the other in-game sounds too loud.
What I would suggest is downloading a program such as MP3Gain. It's freeware:
http://mp3gain.sourceforge.net
It allows you to nornalise the volume of a whole batch of mp3 files. I'd experiment with a short sample until you're happy with the in-game balance, then run the lot through Mp3Gain. You might have to do it in a few batches, but it can handle fairly heavy loads.