Channel A vs. B - 9V vs. AC Adapter

[Bearcub_RI]

1st post ~ go easy on the Cub ;) : Recently purchased the Mens Holiday Special (corona, base ring, mid ring, prostim, PES Box and leads) - overall very happy, and I'm sure I have much to learn... So MANY possibilities!!
Topic 1: I've seen a couple of posts regarding Channel A vs. Channel B intensity (or balance of intensity) when used together, but I was unable to locate a definitive response.
I do notice that Channel B seems "muted", somehow less balanced (Channel A much higher intensity).

Current configuration is CH-A: prostim (yellow) / base ring (green) and CH-B: corona (red) / mid ring (black). I've tried different combinations but consistently find the Channel B to be much less intensity than Channel A. Now: IF I depress the red "cut" switch on Channel A, the intensity *instantly* and *substantially* increases on Channel B. Release it, and Channel A becomes much more intense, and Channel B is "muted" again. I've only tried this configuration with a freshly installed 9V battery as a power source. I've not yet had the opportunity to try the AC power adapter.

Question 1: Am I testing the limits of the PES box by using 4 electrodes simultaneously? Would the recommendation be to use fewer? Or, am I missing something in my current configuration that would help to better balance the two channels?

Question 2: Would there be a noticeable difference in balance if I were using the AC adapter for a power source, rather than 9V battery?

I will continue to try different configurations... I just wanted to pose a couple of questions to the more experienced group.

Very pleased with my purchase, and appreciate any comments and input.

Happy Holidays to all,

Bearcub

[Stretch6]

When depressing ONE of the two channel shut-off buttons (Momentary OFF), shouldn't some sensation be felt between the remaining, both black and red wires interrupted, hot wire (green) and the ground (black) of the interrupted circuit? This behavior, I can check it with a voltmeter at some future occasion, suggests that the grounds of the two circuits are isolated (not COMMON) from each other and switched with the momentary OFF push buttons.

Seems to me that a simple field adjustment with a soldering iron could cure that lack, provided a schematic/board diagram were available

Using one ground as common and having both channels operative would allow a greater current flow than splitting the current flow from one HOT lead between two grounds. It would take a higher voltage to achieve the same current flow.

Any comments? I have a pretty good electronics background.