Volume knob not working correctly


I have owned an Up2Stream 2.1 board for a few months. After updating to the new firmware (4.6.415145.35), all the problems I had before seemed to be fixed. However, after weeks of no problems, I still had the problem of not being able to control the volume. Turning the potentiometer, adjusting the volume in the app, nothing helped. After restarting the device, I had regained control of the volume. But only through the app. Turning the potentiometer decreases the volume no matter which way I turn it. Downgrading to an older firmware had no effect, nor did updating to the latest after that.

Is there anyone out there with the same problem? Or with an idea what to do about it?

With kind regards,