Google Voice Won't Listen

[yairtzur]

Hello,

I have a Galaxy S5 and Google Now is active.
For some reason, many times when I say "OK Google", it delays some seconds and the localization icon blinks, but then it just stops and it won't hear my voice.
It doesn't even hear my "OK Google" again until I reopen it, and then it happens again most of the times.
I noticed that it happens more frequently when I'm home.

Any reason for that? Any idea how to resolve it?

Thanks!