First of all there is no Arc (Gen1) as no new Arc has been introduced. That said you have an Arc. Period.

The Arc is only compatible with the Sonos App controller version formerly known as S2 controller 

The Sub (Gen 1) is compatible with the Sonos App controller version and S1 controller version

You must use the Sonos App controller version to be able to connect to your Sub. If using the S1 controller version the Arc will not see your Sub.

All said which version of the Sonos controller are you using?

Oh thanks for pointing that out I am using the Sonos app, there is no number on it, I tried using the s1 and it kept taking me back to my original app Sonos.

jo

I must also say I’m not really that technical 

jo

Have the Arc and Sub connected in the past or is this a first time setup?

This is the first time 

jo

 Look in Settings ( gear icon ) - Manage ( to the right of Your System ) - About Your System.  Make sure the Version is the same for the Arc & Sub.

Moderator edit: removed serial numbers

Hi,

I can not see what version my sub is as it’s not on my system as I am just told sub not found.

would the issue be with my arc? 
 

jo

https://support.sonos.com/en-us/article/reset-your-sonos-product

 Did you Factory Reset the sub then look for it in the app?  It would then be like adding a new product.  The problem is not likely the Arc.

1. Make sure you can see your Arc in the controller on your device.
2. Next Follow the steps in the 1st link under “All Other Sonos Products” to Factory Reset your Sub. When successful the Led on sub will flash Green.
3. Then click the 2nd link to add your sub

• https://support.sonos.com/en-us/article/reset-your-sonos-product
• https://support.sonos.com/en-us/article/add-a-new-product-to-an-existing-sonos-system

Yes I have don’t that and light is flashing green but still can not be found 

Jo 

I have managed to connect it now, thank you so so much for your help.

jo x