LR Baggs Control-X Preamp - Manual (Page 6)

this happens you will need to change the phase of the X-Bridge when playing with this setup.
Now, if you find yourself using different outboard equipment and you prefer the one amp/two channels setup, the phase relationship will likely
become "chop suey" and you'll probably never be able to detect phase conflicts. However, if you do want phase control each time you play through
a different amp, switching phase on the guitar will become a chore. In these instances, we highly recommend our Para D.I. outboard preamp, which
has a readily accessible phase switch and five-band EQ.
Ground loops: If you are using two amps and hear a hum, chances are you have a ground loop. These should be handled by using standard studio
ground loop elimination techniques.
Trim pot: Next to the phase switch on the Ctrl-X circuit board is a trim pot. You can use this to control the output level of the magnetics. This should
be a control that only needs to be set once, but feel free to experiment. A small screwdriver works well for adjusting this.
Battery: Ctrl-X should provide approximately 1000 hours of play time per nine-volt battery. When you start to hear unwanted amounts of distortion
on the X-Bridge signal during hard strumming, replace the battery. Even if the battery is totally dead, the stock guitar is always available by flipping
the three-way switch to "magnetics only." To change the battery, simply remove the pickguard screws to gain access to the control cavity and
replace the single 9V with a new none. Be sure the new battery is secured in its clip and will not rattle around once the pickguard is replaced. TO
conserve battery life, unplug the guitar when it is not in use. Remember, if the guitar is plugged in, Ctrl-X is on whether you're playing it or not.