Hi @imacdonald, thank you for reaching out to us, and welcome to the Sonos community. I appreciate you for bringing this concern to us. Let me help you out with this.

First, I'd like to ask some questions to isolate the issue so we can create a path towards resolution.

1. When did the issue start happening?
2. Do you experience the tinny sound when playing the TV or when streaming music?
3. Have you tried changing the audio format? Did you notice any improvements?

Let me suggest the following steps to see if this would work for you.

• Unplug the optical cable from the Sonos Playbase and the TV. 
• Disconnect other devices connected to your TV (cable box, Blu-Ray i.e.)
• Unplug your Sonos Playbase and the TV from the power and wait 30 seconds before you plug them back in. 
• Reconnect the optical cable to your TV and the Playbase. This is to ensure that all the connections are fully seated.
• Test the audio.

Let us know how you get on with the advice above and submit a diagnostic report for us to check. Just include the confirmation number in your response so that we can look up the information.

If you have any questions about this. We and the community are always here to help.

Thank you. I have been in touch with Sonos Support and the diagnostics are clean. Redid Trueplay and there is some improvement. Will continue with your recommendations.  

Hi @imacdonald, thank you for your response and for reaching out to our Sonos Customer Care support. I'm glad that there's an improvement with the sound from your Playbase. 

If you encounter any issues, just submit a diagnostic and let us know the confirmation number for us to check what’s going on.

Please do not hesitate to reach out or create a topic if you still have further questions or concerns. 

The Sonos Community is always here to help.

Final Update: 

Today I did a factory reset, reestablished the Playbase unit, and did the Trueplay tuning exercise. I’m happy to report much improved sound. Thank you for all your advice. Case closed.

Ian

Hi @imacdonald, thank you for your update. I'm glad that the audio quality on your Sonos Playbase has been resolved.

If you encounter any issues, just submit a diagnostic and let us know the confirmation number for us to check what’s going on.

Please do not hesitate to reach out or create a topic if you still have further questions or concerns. 

The Sonos Community is always here to help.