Roland SCB55 revision 00 has a problem, namely the left and right channels are swapped. Some boards came from factory with wire patches that reverse the channels and later revision 01 swaps DAC output lines going to WB header... but there's a different and better way to do this, and I am unsure why Roland didn't do it that way instead...

The DAC chip used has a pin that controls left and right channel ordering, and I simply changed it to different state, with a result where one almost cannot tell anything was done at all ~

DAC removal :

LRSEL signal changed to different state :

DAC put back, one almost cannot tell anything was done :