What is this strange high frequency resonance in my room?

[paurey]

Hi,
I am fairly new with REW but already done a lot of progress last months. As you can see below, there is a lot to be done in my room.
I have managed to improve the low frequency part, but I still cannot find out what is this HF resonance (around 9-10 KHz) in my room and what can I do to treat it. I haven't seen anything like that in all what I have read/seen so far. Any help or tip is very welcome.
Cheers!

 

[jschwender]

Are you sure that this is an acoustic signal? It does not decay over a long period of time, i suspect EMI.

 

[ddude003]

Give us a little more information about your system (source, amp, speakers) and room... And post the .mdat file...