"Have I sorted out the problem with the ARC PRO" ? Yes and no.
The problem only exists with the ARC AIR powerbase, and yes I have.
I Started out with the ARC AIR , which you Dr. C in the previous entry has finally pointed out basically that you can't run some analog cars on without interruption because they draw to much current. I think that you've perfectly identified the problem. Please see previous Dr_C post.
Cant think of more than one time that my scalextric cars randomly stopped and the started a few seconds later. So to answer the question, I had to upgrade to the ARC PRO , and switch it to analog mode to eliminate the problem. It was thought that by upgrading to the ARC PRO I would be able to plug in 2 power supply's and overcome a power shortage. However it turns out that just the one 15v 4 amp power supply is needed, SCALEXTRIC US part # P9303, Because the ARC AIR has protection limits that trip when enough power is being used by cars that draw more power...... SLOTIT , NSR.
Need to thank Oliver with Professor Motor ( in the US ) for his customer service and help. He's been very patient and eager to help solve this issue for me.
In my opinion , if your interest in slot car racing is Analog or Digital both types of cars work best with the ARC PRO system Don't even bother with the ARC AIR.... Go directly to ARC PRO and don't forget to switch it to analog...... teeny tiny switch on left side of power base.