If it's a glitch, try the patch downloads, if you haven't already. Still, this is what the guide says about Dampened Spirits, "You begin this quest with the previous objective (Loud & Clear) already active. Leave the Ragged Flagon and find Maven Black Briar. You can be as flippant or sycophantic as you like in your responses to this ale baroness......" I found her upstairs at the "Bee & the Barb". Also, In Loud and Clear, did you burn 3 beehives, steal the queen bee statue and get the Bill of Sale? Maybe the lack of one of those could have prevented progressing. If finding Maven and it won't begin Dampened Spirits, then yeah, I would go back to a previous save unfortunately.