I have noticed a sound difference between some studio tracks. Does Replay Gain work on all tracks if it's been ticked? If it doesn't then I'm going to have to run them all through a Replay Gain program.
replaygain only does something if it has the replaygain metadata in the tags, so yea you have to run it through a program to calculate replaygain and add the tags. GMMP does not calculate anything rg wise or analyze the song