I'm replacing my holding tank discharge hose this spring, Its the original, its in rough shape, and it smells. Should have replaced it last year, but I didn't (lazy, sailing, other fix it jobs, crappy job, pick your excuse). Replaced the hose from the head to the holding tank and it made a big differance to the smell in the head. I used and will be using a white hose that is less rubbery and more sort of plasticky than the black metal spiral reinforced hose( all that because I can't spell non-per...perm...whatever).
I got our CS30 two years ago and I know you just got yours last season so I thought I'd pass on some problems we discovered to you It might save you some hassles. But I'll do it on another post before this one times out.