Sudden wave drop

Does anybody know what could a sudden wave drop mean? I use mind monitor (muse monitor) app and sometimes this happens. Is it due to a bad fit or is it because of something else? Here’s a picture of the waves drop.

Hi, I have had also experienced similar drop. In my case I suspected it to be due to 2 devices (my phone and iPad) having a contention over the data transmitted from Muse. As both had muse monitor installed. Therefore I disable BT in one of the device, and that have seemed to stop the drop.