Can Still hear music when amp is muted

I was listening yesterday and had reson to hit the mute on my NAD C350, i was surprissed to find that i could still hear the music very faintly, and that if i turned up the volume it got louder, i never noticed this before, do you think there is something wrong with my amp, or is this normal?
It is normal. Some manuf. mute function completely blocks the output and others just turn it down so you can answer the phone, etc. This is the latter.
It is normal. I have one with two mute settings on the remote. One soft, the other off.