Sonos Arc

Are you strictly on wifi or are any of your speakers connected via ethernet cable?

wifi only, all speakers

Have you reset your router?

Do you have the ability to connect one of your Sonos speakers to your router with an ethernet cable? This will create a SonosNet mesh network and can oftentimes improve the network performance from your speakers.

I will be able to do that tomorrow. Do I need to keep at least one speaker connected with an ethernet cable at all times or just temporarily 

Only one speaker needs to be connected at all times.

Here is more information: https://support.sonos.com/s/article/3209?language=en_US

NOTE: The one speaker cannot be the Sub or surround speakers.

Thank you. I will look to perform this task tomorrow and provide update. Thanks again. Happy New Year. 

If the SonosNet solution doesn’t work, you could try changing the WiFi channel on your router.
https://support.sonos.com/s/article/4769?language=en_US

Changed the channel and still having the same issues. Unable to direct connect one of the speakers this weekend but will hopefully get a chance to do that later this week or next weekend. 

I direct connected ethernet to my sonos one speaker. Seemed to fix problem temporarily but my sonos arc + sub still are not always found or they show up but it takes a while. I am unable to direct connect ethernet to my sonos arc...

This problem did not seem to exist until I added the sonos one to my existing system.  

I have a move, one sl, one, arc, and sub

Is your One and One SL in another room or connected to the Arc as surrounds?

In the Sonos app, go to System > Network and try changing the SonosNet Channel and see if that makes a difference.

No they are in separate rooms. 

I will mess with channels. 

No, problem was solved. Once I direct wired one of the speakers to router, the problem went away. Thank you.