Hi Blazin,
You can do this in a passive fashion. Please note I am not responsible for any mistakes or misprint in my description. If unsure, contact and have a certified tech perform the modification.
You will have to sacrifice two RCA inputs on the back.
Take the output from the volume control (that currently goes to the input on the circuit board) and connect them to one set of RCA jacks on the back of the unit. Mark these jacks "Variable Out".
Now connect another set of jacks on the back of the unit to the input on the circuit board. Mark these "Main In".
Be sure to maintain the proper "left" and "right" channels.
Now you can run interconnect cables from the "Variable out" to any amplifier No need to turn on the Jolida when doing so as you are simple using the source selector and volume control from the Jolida. This provides a passive control stage.
Now if you want to use the Jolida again, you simple run short interconnect from the "Variable Out" to the "Main In" to direct the signal back to the Jolida's circuit.
This also allows you to run an outboard preamp into the Jolida as well by connecting the preamp to the "Main In" jacks.
Be sure never to run a source directly into the "Main In" as you will not have any volume control and damage will occur to your speakers. Sources would be connected only to the remaining unchanged inputs on the back of the unit.