I'm working on a RV3 and need a bit of audio intelligence. I have the following devices which I need to hear. Some are stereo and some are mono. Com 1 and com 2 are mono, EFIS audio is stereo and On speed device is stereo. What do I need to combine these devices in a single set of headphones. Will I need an audio panel so that when there is activity on the com radio the others are muted?