I have a Kenwood VR-309, and the remote controls my 3rd gen RCA DSS with no problems (other than a mis-mapped Enter button -- which is a pain).

Someone else in another thread was having trouble getting their RCA DSS (which sounded like it was 4th gen.) to respond to IR as well.

My guess, then, is that the 4th gen. RCA stopped supporting IR for whatever reason. As I understand it, the Kenwood 309 is just the 209 plus DTS decoding, so I doubt if much changed with regard to the remote and its abilities.

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