I have a Samsung CHG90 monitor and a Samsung Soundbar JW7500. I want to connect an extra Roku Ultra. The monitor does not have a speaker, hence why the soundbar is in the mix. My ports are limited on monitor, but I intend to use the mini-DP(getting a cable Mini-DP to HDMI) port on Monitor. So if I run that to my Roku, that would account for the video. To do the sound, could I plug a rca cable into the remote headphone jack and other end into my aux in on speaker for the sound?
You could, but the remote tends to eat batteries while using the headphone jack. You'd also only get stereo if that matters. You might be better off with an HDMI audio extractor. Also, I don't know much about DP, but make sure the cable works from HDMI to DP. I think the normal use for such cables is to go from a computer/laptop DP output to HDMI monitor input.
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