You can connect the Arc to the TV’s Arc/eARC port or its optical port using the adapter supplied with the sound-bar. I’m not sure what you need for the PS5, but try it on the HDMI port with pass-through/eARC switched on in the TV settings. Your TV user-manual should explain where to find those settings.. they’re usually in the ‘sound-out’ settings on most TV’s.

I’ve not yet (personally) seen a TV with more than one HDMI-eARC port… if the PS5 needs that port, then I suspect your only option will probably be to put the Arc on the optical connection, but it’s audio will ‘likely’ switch to DD 5.1 in that instance. 

HTH

Hi @Fullerboy5 

Welcome to the Sonos Community!

HDMI-ARC and eARC are meant specifically for audio devices (Audio Return Channel), so it seems very unlikely to me that your PS5 would require eARC specifically.

It may be, however, that the only HDMI port on your TV that supports 120Hz is the one that also supports eARC. This seems a bit counter-intuitive, so it would be worth making sure that you have understood this properly by checking your TV’s manual - you did say that you were “assuming” it to be so.

If this turns out to be the case - the only port that supports 120Hz is the only one that supplies eARC - then you’ll need to choose between a 120Hz picture on your PS5, and Dolby Atmos/LPCM audio on your Arc. You won’t get both with that particular TV or without a third-party device (unsupported). If you choose the 120Hz picture, you’ll need to use the supplied HDMI/Optical adaptor to link the Arc to the TV’s optical output, resulting in stereo sound or 5.1 Dolby Digital sound only.

I hope this helps.