The L/R channels on the outputs of the Synth Effects (Wet signal) are swapped on the Sub Outs at Firmware 1.4 level.
They are OK on Main Out.
Recreate:
INIT Preset.
Pan 100% Left.
Load Synth Effect - Delay (or Stereo Delay).
Synch Off
Set Delay (L and R Delay) to 1000ms.
Play a note.
On Main Out - Note and echoes are both on the left channel.
On Sub Out - Note is on the left channel and echoes are on the right channel.
Pan 100% Right
Play a note.
On Main Out - Note and echoes are both on the right channel.
On Sub Out - Note is on the right channel and echoes are on the left channel.