window near my listening point and excessive bass

Hello friends. I have a very small room like 3m(10feet)x2.4m(8feet). I have 12L bookshelf Quads, and Audio refinement amp. My problem is the high level(and boomy) of bass. My speakers are placed at the most desirable place and my listening point is nearly optimum(i dont have many choices since the room is small). One thing that leaves a question mark is that about half area of the wall behind my listening point is window(plain glass:)). There is about 1m between window and my listening point(back of my head).
So is the window creating my bass problem or i have a problem that can not be cured? Also i want to add that wall behind my speakers is completely naked(no damping). Where should i damp? the naked wall behind my speakers or the window behind me or both to decrease bass?

thank you.