DDJ-SX Issues with LEDs, Channel Faders, and Cue Points

Hi, I have multiple issues with my DDJ-SX that seem to have started when I upgraded to OS X Sierra (used w/ Serato). I have the latest firmware in the DDJ-SX and Serato V1.9.6. Here's a summary of the issues:

1. Deck 1 fader changes gain on its own and is erratic otherwise. If the fader is at full volume, backing it off just a tiny, tiny bit causes the track to go almost silent. Bringing the fader all the way down to 0 doesn't silence the track, either. You can still hear it coming through the master channel. Also, changing the fader doesn't actually affect the playing track for several seconds - there is a lag between bringing the fader down and the track actually decreasing in volume. This behavior is isolated to the Deck 1 fader.
2. Channel meter LEDs are completely non-responsive on decks 3 and 4. No matter what track is playing, all the LEDs remain off. I should note that all LEDs work fine during the powerup sequence.
3. Load and FX on/off button LEDs do not work for decks 3 and 4.
4. Setting a hot cue with the blue pads results in a different pad (and cue point number) than the one I pressed lighting up and getting stored. This was initially isolated to decks 3 and 4, but now decks 1 and 2 exhibit this behavior as well.

Would love to hear if anyone has any insight. It's pretty frustrating trying to DJ with this setup when I can't set cue points properly and have no visual feedback of the track levels.