The reason probably is this unit support three simultaneous Bluetooth connection and if an unknown user device with active Bluetooth comes in the vicinity or someone attempts to connect the device, it attempts to pair and drops the live connection. Had to return them to reorder a size 4. Useless just throw that away and let your computer walk you through the work. I do not have wide feet, but they are not narrow for sure. Feels smooth and Ventilated as these have "THOUSANDS" of holes????. Lo so. I then apply a thin layer of wax following the direction of hair growth and let it sit for about 20 - 25 seconds depending on the room temp. love mine Im one of those awful peeps who made fun of them and thought they were ugly silly shoes. To the trash they go :(