I bought this Central Station new in 2013. It still works fine.

Note: The Central Station for sale does not include the CSR-1 Central Station Remote shown on the manufacturer's website and in the manual.

Overview (from the manufacturer's website)

When you want to switch between multiple sets of monitors and multiple analogue and digital sources and hear exactly what your mix sounds like, with no coloration, you need the PreSonus Central Station professional monitor controller. Its audiophile-quality, passive signal path, with no op-amps or ICs, and its S/PDIF inputs with 24-bit, 192 kHz D/A converters ensure the sonic transparency pros need.

Easily switch between three sets of stereo, analogue input sources and one stereo digital input source and audition them with up to three pairs of speakers, with individual trim pots for each speaker. You also get two screaming-loud headphone amplifiers with individual level controls. If that's not enough, connect the line-level Cue outputs to a headphone distribution system, such as a PreSonus HP2, HP4 or HP60.

We've included plenty of extras. Talk to the musicians over the headphone and cue buses using the onboard talkback microphone, or connect a dynamic mic to the XLR Talkback input. A footswitch input enables hands-free talkback operation. A Mono switch sums the stereo source to check for phase problems, and Dim and Mute switches let you reduce or mute the speaker outputs without changing the main level knob.

With its I/O, audio quality and features, it's no surprise that the 1U rack-mount Central Station PLUS is the pro's choice for monitor control.

Info: https://www.presonus.com/products/central-station-plus-monitoring-controller

Manual: https://www.fmicassets.com/Damroot/Original/10001/OM_2777400201_Central-Station-PLUS_EN.pdf?_gl=1*17o95n8*_gcl_au*NzExOTU2MDg1LjE3NTIxMjYwNzE