We all used classic Alps, ITT,… style switches to switch sound.
As long as you stay on local cards, they may be sufficient, but when you need to control remotely by logic or microcontrollers, you must either use relays or analog switches. We knew the SSM2402 which is no longer distributed nowadays.
I just tested the DG403 successfully. It is powered by +/- 15V like conventional AOPs. It can be driven in TTL or Cmos Interestingly, it is composed of 2 NO and 2 NC which allowed me to wire it as an inverter. We therefore have 2 inverters with independent controls. By this system, the track is grounded when not in use, this avoids picking up parasites. There are also 22K pull down resistors which prevent even at small residual potentials causing "peak poc" during switching.
The small PCB that I made is quite ergonomic by bringing all the connections to one line. This allows me to place a bar at a right angle. If more than one DG403 is used, they can be BUS powered. There are straps on the input, by removing them and placing a resistance, I can create an input attenuator. On the output there is also a series resistor which can be used for summing but can be bridged for other uses. The control resistor is a 10K.
There are many applications: switching sources, muting, matrix, etc.
If you are a PIC enthusiast, you can program your switchings without limits while keeping the DG403 as close as possible to the input connectors.
Personally, I used the Vishay DG403DJ-E3 which seems to me a good compromise for the price (+/- 2.5 €)