I own a 2008 44 Sundancer that has had this ongoing problem since last spring. It seems to be the strongest in the compartment where the salon AC is, in fact when that AC unit is on it intensifies the odor. I have tried just about everything. Bilges and sumps are spotless, there is no sign of water or mold. This issue has plagued me the whole entire season. The boat has been out of water since early October and still has this odor. Since it's below freezing here in the Northeast I suspect that this is not organic. Any suggestions or recommendations would be appreciated? Also, has anyone else had this sweet odor? It's not your typical boat smell. It's not musty or foul like from a bad waste hose. Thanks.