The 2X A/B module is an utility grouping two independent “A/B selectors”:
In the upper part, a passive A/B switch with output attenuators and a latching switch (with position “off” retention), with led indication of the selected output
In the lower part, a passive A/B switch with a multiple on each output and a latching switch (with position “off” retention), with led indication of the selected output.
If no jack plugged on lower “IN”, the upper signal as routed on upper and lower part. (alternative version)