Hi Lee Weng Keong,
Thanks for your post and welcome to the community. I am very sorry to hear that you are having issues with Volume adjustment inside the app, however I would love to help you with this.
Firstly, I would recommend deleting and reinstalling the Bose Music App, if you are using Spotify please ensure that you don't have both Spotify and the Bose Music App open. A product reset may also help the Soundbar resync with the Application, this can be performed via:
Please update us on the results of these steps.
Hector B - Community Support
Hello Lee Weng Keong,
Thank you for trying these steps for us.
Would you be able to let us know what firmware version your Soundbar is on? This can be found within the product settings of your Bose Music App, as well as ensuring your App is also up to date.
I look forward to hearing from you!
This is a known issue that is currently being worked on to get resolved. When using the Bose Music App with a Soundbar and Home Speaker, the audio adjustments are labeled incorrectly. The “Speaker Level” slider adjusts the bass level and not the speaker level. Conversely, when a Bass Module is connected to a Soundbar, the "Bass" slider adjusts the speaker level and not the bass.
The sliders work correctly in terms of adjusting audio, only the labels are incorrect.
This will be resolved in an upcoming software update.