We get this all the time at all hours of the day and night.

I got a call from 408-703-6157 as just like other #'s from California, Globe Az, Phoenix Az, Mobile Al, ect. and no one will say any thing. I answer the call with HELLO and no one will say any thing or I don't answer and they don't leave a message.  I say to the caller if you don't want to talk don't call back!!!!!

I too got a silent phone call from this number. It was on 8/13/2013 at 3 am central time.

Two calls from 4087036157 at 5:01AM EST.  I didn't hear it.  No voicemail.

phones in middle of night.  dead space.  noone there.   grrrrrrrrr