I'm looking for MOTU 2408 mk3 schematic. The interface has some problems with the headphone amp but I found out that there are some quite strange voltages in the circuit. Several opamps have 4.5V on the output, the 7906 IC gets only -5.8V on the input(it should be at least -8.5V there), the audio part is supplied with +9V and -5.8V (it seems to me that the voltage should be symmetrical). It looks like ether there is a shorted circuit, or some problem with a power supply. There are 4 bridges and several stabilisators so drawing the schematic is not that easy. I asked about it on MOTU forum but the guys there know nothing about power supplies, they know a lot about operating system driver but it's not what I need.
Mark
Mark