I've acquired two 8-channel Tascam DX-8 DBX units (long story).

They both state the model number on the front panel as being "DX-8 DBX Noise Reduction Module", and yet one of them has a stock "bypass" pushbutton for each channel, where the other has a single stock button for this function.

The serial number of the unit with the pushbuttons is 44081, the serial number of the other is 80366. Judging from the serial numbers I could guess that the higher number is the newer unit, but can anyone advise which is the newer of the two units?

Also, on the unit with the pushbuttons, someone has installed a toggle switch below each pushbutton. The toggle switches are connected directly to pins on the "Remote" connector on the back panel. This remote cable is the "umbilical" cord between the DX-8 and the Tascam 80-8 recorder series. I'm presuming that these toggle switches are intended as redundant "FUNCTION SELECT" controls for the connected 80-8 recorder. I don't have the schematics, can anyone concur on this?