LG V20 - Alarm vibration doesn't work properly when under pillow?

[AC Question]

I have to keep my phone under my pillow for the alarm clock so I can hear it when it goes off (I'm hard of hearing, I won't hear the phone if it's anywhere but directly under my head when I'm asleep); But the problem is... The vibrator doesn't seem to work properly when it's under the pillow, i.e., it makes really super short really weak "puttering" pulses instead of the standard long vibrate, pause, long vibrate, pause, and so on. As soon as I take the phone out from under my pillow it vibrates normally. I suspect either the proximity sensor or the light sensor is causing it to do this as when I place my hand over the sensor in the top left of the phone it starts to do it again until I take my hand off. Is there anyway this can be fix? I'm oversleeping because the phone won't vibrate normally and consistently when the alarm goes off.

 

[Tim1954]

Put it on a metal plate, cooking pot or similar in the bedside table. The rattle will wake the dead.....