I recently noticed that a few HX3 boards and MIDI expanders built between April and July 2015 left our manufacturing with a bad "brown-out detection fuses" setting of the internal AVR microcontroller.
If your HX3 does not start up (just with blocks on display) or forgets various settings (even licence numbers), it is certain that its controller ran amok. Normally the microcontroller should reset itself when DC power sags below a certain value, but without proper brown-out detection it may do very strange things when voltage is too low; it may even change it's own firmware to an unusable state. It depends on part tolerances if it will do harm.
As a quick fix for lost licences or bad parameters, you may restore factory settings (including licences) by holding encoder knob pressed while powering on. Press "up" button to acknowledge restore.
However, wrong brown-out detection fuses setting should be corrected by us or any service representative with a special ISP programmer. It cannot be altered by a firmware update. It's only a 10-second job, no data is changed or lost. We will refund shipping costs to your nearest representative if your HX3 is affected.
For OEM and technicians: Connect DIAMEX PROG-S ISP programmer to PL1 ISP of HX3; note the pin 1 direction. Power up HX3, start HX3 Remote #3.9 and go to "Advanced" page. Please verify that number entered in "DIAMEX COM Port" field is the same that was assigned to "ERFOS-PROG-S" COM&LPT device in Windows device manager. Click "Repair Fuses" button at bottom of page. Message window should tell if AVRdude was succesfull. That's it.