Ha, I'm glad you said that! I thought it was some program delaying the boot. I checked the usual system programs that list delays. Nothing.
I deleted my antivirus, thinking they're the ones to blame most often. Nope. Reinstalled MB drivers. Nada. USB3 drivers? Negative.
Some BIOS setting? Maybe but I have no way to tell.
Oh well I hope the next BIOS release will fix it.