I looked at http://www.samsung.com/us/support/owners/product/2012-40-lcd-tv-e550-series and the red white jacks are inputs to the TV not outputs.
Options look severely limited on this model. If you are using HDMI input from some source you want a sound bar with HDMI in and out or an HDMI Audio Extractor. Examples:
https://www.amazon.com/Extractor-Splitter-Output-Optical-Digital/dp/B01I9JG70A/
Just need some advice, I have an external sound bar and a Samsung LN40E550F7FXZA tv from 2012. The tv only has 1 HDMI port, no Digital Audio port, and some analog ports. I currently have an analog audio (red and white) connected to the tv and running through the AUX input on the sound bar but there's no sound. The tv has no option to switch to external speakers either! I'd really appreciate the help, I feel stuck :/

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