RCA to HDMI is hit and miss and since Samsung didn't create RCA to HDMI convertors you have to ask that maker what's up.
I doubt the Smart Hub will do much with an HDMI input here other than let you switch to it.
A cheaper fix would be a DVD or BD player with HDMI output.
My Samsung smart tv's "smart hub" doesn't recognize my Sony cd/dvd changer. The old changer has RCA cable plugs, but I bought an adapter to convert RCA to HDMI. Still nothing. Any help would be appreciated.

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