I've completed "Loud and Clear" and cant start "Dampened Spirits". I do not have a revert save to a point before i turned in Loud and Clear, or before i broke into the mead place to do that one quest where you shut down the drug cartel being run from there, so what am i supposed to do to continue the Thieves guild, i really wanted to do them.

I'm not sure what triggered this issue in your game from the details you provided, but it could be one of the following:

• If you break into the Honningbrew Meadery before receiving this quest, the quest "Dampened Spirits" will not start properly due to a bug. There is apparently no solution to this bug for Xbox 360 players.
• After completing the quest Loud and Clear, if you do not ask Brynjolf why Maven Black-Briar is requesting a meeting, the quest will not become available. Also Brynjolf will not speak to you, saying only that he has "important tasks to be doing". This was apparently fixed with the 1.4 game update, but the fix may not work, if your game was started prior to the release of this patch (~February 5, 2012) and/or the bug has already occurred on that saved game.

Unfortunately, with these type of bugs, there is sometimes no solution, except to reload a prior save (which you said you don't have) or start a brand new game making sure you have the latest game update installed from Xbox Live (which is currently version 1.9).