Alex,

Probably won't take away from your 'fishing esperience' but it will eventually ruin your fly line.

Yes, you need to fix this. Take ALL the fly line off, cut off and then remove the excess backing, and reattach and then respool the line.

However, BEFORE you do this, make sure it's the 'extra backing' at fault, and not the reel operator. Are you spooling the line evenly onto the spool as you reel it in? You do need to work it evenly back and forth as you reel, so that it fills the spool properly and doesn't pile up in one location. Check that FIRST, and if it's till rubbing, then just take a few minutes and fix it.

Good Luck!

Buddy