Try another parallel cable.
If it works in manual, it is the computer, cable or breakout board.
In the machine, give all the crimps a bit of a tug. That's on the cable between the BOB and the motor control.
Turn off and remove power before fiddling, so that the smoke does not get out. Hard to get back in again.
No need to check front panel stuff if it works in manual.
Do you have a backup copy of your Mach3 config file (xml)?
All the steppers still work properly?