Sledge not receiving MTC from Logic for Arpeggiator

[goldtop68]

I'm trying to sync the internal Sledge arpeggiator to Logic Pro X. It receives the notes fine but doesn't work when I transmit the keyboard (Keylab49) to the Sledge. Setting it to Midi Int or Auto, the Sledge triggers the arpeggiator fine, but when set to external, both the Sledge Keybed and the Arturia one transmit notes but in what seems like a much slowed down arpeggiation, almost to not work. Like I hear the attack, but then sort of a sorry modulated version of the quick attack sound,

Anyone come across this? Suggestions?

Bob