Serato locking up when connecting DDJ-SX2

When I fire up Serato with the DDJ-SX2 plugged in and turned on, it locks up before it can read and switch to controller mode. I have to force quit Serato, then re-open Serato and it works.

The same thing happens when I fire up Serato and THEN power up the SX2. It locks up until I restart Serato and then it works.

All versions and firmware are up to date with both Serato and the SX2. This has just started happening recently.

Thanks

Any ideas?