Hello, PioneerDj team!
Being a happy owner of a DDJ 400 controller, I've discovered a strange behaviour of Highpass Filter (no matter, whether the controller is plugged in or not).
Instead of cutting lows it begins to slightly cut highs (but it is anyway noticeable) until the moment when the knob reaches 1 o'clock position (or near that).
The PARAM is completely switched off, because I don't need that resonance thing, so this knob is turned all the way to the left.
I'm inclined to think, that this is the software issue. Besides some users had a similar problem on DDJ 1000 earlier, which seems to be still unsolved.
Here's the video of how this happens and sounds:
https://youtu.be/2yzRCzdIM8Y
I have the Rekordbox v.6.5.2 rev.21393-18825-18786 x64 running on Win10.
Hope to get any help or advice from you!
Best regards,
Sunn Jellie