Hi. Regarding balanced mode, the V2's instructions say at one point:
"By incorporating a TRRS to XLR cable, the Geek Out V2 can be connected to a home stereo system in full balanced mode."
However, suppose I have an older home stereo system. I'm guessing that the left and right channels share a common. If so, will this defeat the purpose of the balanced source?
You are correct.
If your home stereo does not include a 4-pin XLR input or a pair of stereo 3-pin XLR inputs, then this would defeat the purpose of using the Balanced output on your GO V2
I do have balanced headphones and I do have balanced inputs on my stereo and I highly favor balanced over single-ended. I have the ability to plug the same headphone into the SE port and then the Balanced port to compare. It's a profound different on many recordings.