Need help with musty odor

[schad]

Hello, I have a 2014 Passport 195RB that I bought 2 months ago. I thought I smelt must when I looked at it (private sale) but figured it was due to being shut.


I brought it home and could not lose that smell..it was in the bedspread..which I washed a number of times to lose the odor.


I went camping for 2 weeks. Hung clothes in the two closets next to the bed only to have all the clothes wreak of must.


I am very concerned as I do not see or feel any wetness anywhere on walls of floor of the cabinets. The pass-thru storage compartment is underneath the closets yet I see not signs of water there either. I hung a damp rid bag in each closet and within 5 days there is about and inch and a half of water in each bag. I put in a brand new mattress and need to find the problem as I don't want this odor to get into that.


Can anyone please help me to figure out this musty smell. It is sending me over the top.

Thank you