This scenario reminds me of all the SCSI voodoo of the early Macs, nevertheless, I do think the problem lies with either the Isaac software and/or the iBike Gen 3 having compatibility issues with Apple's latest OS or software conflicts with PowerAgent and/or Golden Cheetah (both software packages use similar drivers).
Is anyone having software/hardware issues also? I would like to continue to use the Gen 3 iPro, as I have invested considerable money, time, and effort just getting the quirky little thing to give me dependable and reasonable power numbers (Road & TT bikes) under most circumstances, i.e used a DFPM to get a proper profile(s). I am not really interested in upgrading - unless, of course a trade-in value is offered on a new PowerPod

Any suggestions?
btw. I do have a PC desktop with the latest Windows 10 OS - I will experiment with it also. Unfortunately, I travel a lot and need the iPro to work consistently with my MacBook.