Hello,

i have just uncovered the following bug:
I picked up Rjorn's drum before getting the quest to get it.
After turning in the instruments to the bards guild, i still have the task goals "Find Rjorn's drum" and "Find Finn's lute"in my journal.
The stage of the quest to get the drum was 0.00 after handing it in.
When i tried to remove the goals with the console command "setstage bardscollegedrum 200 1" i received skillups as a reward, even though i had already had the rewards before.
So now i got rewarded twice for the same quest.

I wouldn't call console commands to be a "bug:exploit". It's either cheating or advancing a stuck quest, depending on how you look at it.