@Sudin 

We here are talking about the NC200 model I believe...

Although the NC200 has sound when remotly viewing, this model does not support sound detection.

This is backed up through system settings with no sound detection options.

Thank you anyway

Mentioned same problem on NC200 on v.2.1.8 , upgrade to NC200_2.1.11_Build_200508 fix it (this issue ;) )

@zsvo ...well, here it is...
You are absolutely correct, as you know :-)
Credit must be given where it is due, and corrections must be made where they are required, the universe demands balance.

Much to my surprise, TP Link have clearly addressed this issue.
I take back my previous comment that TP Link were asses, and indeed most of the other crap I wrote in my frustrated state of mind earlier in this thread (#10).

I was wrong.

Thank you for the heads~up zsvo! You are my hero this week :-D

Thank you for addressing the firmware issues TP Link thus proving, I was the ass...

Peace.