Hi @Bluesriff7, Thank you for reaching out and welcome to the community. Thanks for bringing this up and I know where you're coming from. About this issue with your Sonos Arc and the Sub, there should have an option on the Sonos App on adjusting these settings, Kindly check this article about Setting Up Sonos Sub for information. Also, for us to check on this issue. I’ll ask you to submit a diagnostic report to investigate further and check the status of your Sonos system. You may reply to the thread with the confirmation number to assist you with this issue. 

Please, feel free to let me know if you require any further information.

We're here to answer any further questions you have.

Diagnostic report 1904091149

Hi @Bluesriff7, thanks for the update. And for sending a diagnostic report. Upon checking the diagnostic report. I can’t see any issues with your Sonos system. Have you tried to check and adjust the Sub level settings on the App to check if there are any changes. 

Let us know what you have in mind with the advice above.

The Sonos community is always here to help.

I have not got a sub at the moment. I was thinking about adding a sub

to my system. It was the way I asked the question, making you

think I had a sub. Sorry about that.

At least I know the arc is working ok.

Hi @Bluesriff7, thanks for the update. Thanks for the information that you provided. I apologize because I’m under the impression that you have the Sonos Sub already. It is possible to adjust the Sub level, and there is an option for it on the Sonos App where you can use the slider to increase or decrease the volume of the Sub audio to match your preference with the Sonos Arc. I hope this answers your question.

If you have other questions with your Sonos products, feel free to reach out.

The Sonos community is always here to help.

As you do not have a sub, goto the Sonos App “Settings/System/tArc Room Name]” and select the EQ option under the sound heading and in there you can adjust the Bass slider bar and Loudness option to reduce/increase the bass.

Also note that when listening to ‘TV audio’ there is a ‘Night Mode’ option on the Arc’s ‘Now Playing’ screen that will reduce the intensity of loud sounds, while increasing the level of quieter sounds, making dialogue clearer, without having to turn up the volume. You may find that feature helpful too.

Thank you for all the information you both gave me. 
Its been very helpful .