As Woojer Edge is driven by sophisticated software, this may be caused by a software "glitch". It can happen for example when switching the audio source from Bluetooth to 3.5mm. If you're experiencing such behavior, you should hard-reset your device. For Strap Edge - please refer to the following article, and here you can find the hard-reset instructions for the Vest Edge. 

Hard-reset Woojer Strap Edge

Hard-reset Woojer Vest Edge