XDJ-1000s running slow - especially with more than 2 connected

I am running 3 XDJ-1000 MK1s and a V10 and high end new Windows 10 PC with the newest version of rekordbox. It's all connected through a ethernet netgear switch.

The lag is unbearable. I'm using export mode and I can barely use the interface. The problem gets worse when I use 3 XDJ-1000s instead of just 2. If I use a thumb drive, it's no problem even to synced devices. It used to be very fast, I don't know what changed.

I am also having a problem when I search from the XDJ, if I select an artist it doesnt show their music like it used to. Search by track name still works.

Please help.