The 2KHz dip is Mid Range Compensation... Courtesy of the BBC. XP (thats the Mr Ick Face!)
Below ~250-280Hz in your graph,
@Sachb , is where your room is acting as a resinator.
Which are you talking about?
You can turn MRC off using the Aud App.
You cannot turm off the Schroeder Frequency of your room. That... you have to use guile and Acoustics to make your friend!