I did find my genuine MB hose, it has been gathering dust since my rebuilt hose works fine. I am convinced the buzz you and others have described it due to the lack of orifice inserts (lack of a better name) in the rebuilt hoses. Notwithstanding, I would put up with some buzzing if it cost me 1/7 the cost of a new hose. If you are interested in the genuine article, let me know. It is available.

K

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1999 E320 (gave to daughter) 250K
1994 F150 (may be the end of its road) 240K
1989 560 SL (Reassembly after paint job) 160K
1986 560 SL (deceased., gave it's life protecting my wife)
1988 300 TE (departed)
1994 945T (still running strong with an upgraded cam) 349K
1986 242Ti (deceased)
1968 GT500KR (under restoration)