Well, as luck would have it, I get a beautifully clear night for the first time in ages, grab my gear, head to the marvellous site five minutes down the road, set up...and then the issues started.
Short version - the iPolar scope, or maybe the software, is playing up.
Longer version...I have an iOptron CEM26, the one with the integrated iPolar scope and stainless steel tripod. I usually pair it with a modded Canon 60D and a WO Redcat 51. It's portable and not too much of a hassle to set up.
Tonight, with clear skies beckoning, I went through the iPolar routine, managed to "Confirm Position 1" and then the fun started. The iPolar scope appeared to keep "looping" through the same process. It would detect stars - in numbers like 19, 24, etc. - then tell me "Plate Solve Failed", as a screen full of stars winked in and out on the software. It was going through this looping process over and over about every half second.
I did the obvious and rebooted everything, took a new dark frame, etc. Same result. I checked connections, USB hub, etc., and rebooted again. By my watch, it went through the same looping process for almost 25 minutes. Way too long.
I've checked, and I'm using the latest version of the iPolar software. The scope is an integral part of the CEM26. The mount was levelled, the load balanced, and the optional GPS module was (initially) fitted to aid in proper positioning. Environmental conditions were good, seeing was good, no cloud, and only the faintest of breezes. Almost perfect conditions (
sob!)

I should add that the laptop has the permissions set to allow communication with the iPolar.
Does anyone have any ideas, hints, tips, or suggestions? Feel free...