Before you connect your StreamBuds Ultra Dots to the MIXX Control App, you need to connect the StreamBuds to your audio device first. For assistance with this you can find the article here.
Once you have connected to your audio device you can open the MIXX Control App. On the first screen your Earbuds should appear and you'll be asked if you'd like to connect them to the app. From there you'll be able to access the Homepage where you can customise your controls and more.
For further assistance please contact here.