What do they show as in your controller? Are they a separate ‘room’, or do they still show up as +RS +LS?  What source are you playing when they sound different? Is it Dolby Digital, or stereo, or what?

Have you changed the setting from Ambient to Full?

Thanks for the questions and tips. Well I have zero idea how but the sound is back to normal (rear speakers are more surrounds as opposed to acting like main speakers). Obviously not watching anything today while at work, I turn it on tonight and presto it’s back. Didn’t change any settings beyond removing and re-adding the One SLs. 
I think it had to have been a source issue as movies and other video content yesterday evening were playing like it was stereo music. Some weird glitch with Apple TV most likely.

thanks again I can tell this is a helpful forum!