There is the possibility that you are sending serendipitous commands from the MODX (commands intended for functions within the MODX). When connecting your MODX to any other synth or device via MIDI, it is highly recommended that you use the Zone Master function. The MODX is likely the first synth you’ve owned that transmits on eight MIDI channels simultaneously from the keybed... Zone Master function will allow you to decide exactly what information is transmitted from your MODX to your connected devices.

Without it — you might well find that your external connected device begins to behave strangely.
Are you using the Zone Master Function?

Let us know.

Bad Mister, thanks for your response. The truth is that Master Zone is Off. Should I put it on On? This can cause other things to stop working correctly? That is, I now use the Modx tempo to launch the kronos clapper.

Test question I suppose.

Anytime you want to control any other device via MIDI with the MODX, you want to put ZONE MASTER = ON
then use the ZONE SETTINGS within the Performance

Press [UTILITY] > "Settings" > "Advanced"
Zone Master = ON

Now with every Performance two new screens are available
Go to the Performance you want to setup
Press [EDIT]
Select the PART
Touch "Part Settings" > "Zone Settings"

Each PART will have its own compliment of Zone Settings and Zone Transmit functions.

When you activate the ZONE SWITCH for a PART you can define if it transmits to the INTERNAL PART for that slot or you can set it up to transmit OUT via MIDI from any slot on any Channel.

Int SW - this is where you designate whether or not the internal MONTAGE Part assigned to this slot is going to sound. If you set this to Off, the slot becomes available exclusively for an external device. An internal Part must occupy a Part slot for it to be used as a Zone - you can then disconnect the internal Part with this switch.
Note Limit - this sets the range of notes transmitted by this Zone. Setting the High Limit lower than the Low Limit sets up a "no-fly" zone where notes in between are silent. This parameter affects both Internal and/or External transmitting. This parameter defines what gets transmitted - not to be confused with the Part's own Note Limit which define what gets received.
Octave - +3/-3 octaves
Transpose - +11/-11 semitones
Transmit Ch - this is where you activate this slot to control an external device by selecting the MIDI channel. If Transmit Ch = OFF, the Slot will not transmit OUT via MIDI at all.
Bank Select - if you wish to send MSB/LSB set to ON, and enter values. If you do not wish to send Bank Select set to OFF
Program Change - if you wish to send PC set to ON, and enter the value. If you do not wish to send a Program Change set to OFF
Volume/Expression - if you wish to send/control the zone cc7/11. If you do not wish to send Volume or Expression set to OFF
Pan - if you wish to send a pan position message. If you do not wish to send a Pan command, set to OFF
MIDI Send - when active (green) the Program Change, Volume/Expression, and Pan Settings are sent in realtime from this screen. When inactive, the values are only sent when the Performance program is initially recalled. (Note: Bank Select changes are not sent until the Program Change is selected... This means: changing just the MSB and or LSB does nothing until a Program Change value is selected).

Thanks Bad Mister. For now, just by having turned on Master Zone, I have not had problems with kronos FX. I will watch and I will use your last post as a reference in case any new setback arises derived from this matter.

Thank you!!