Hey MS gurus, I need a bit of help.

As the title implies, I'm having problems with a lost sync issue with MS. Version 2.2 board, MS2/Extra code. With the crank trigger input working, car will start and idle fine, once I hit around 2000 RPM (no load), RPM gauge will drop to zero for one count and then return. Problem occurs at different RPMs, but seems worst right around 2000. I have logged the issue to verify. I'm offered the code 26 for lost sync reason, which doesn't help at all since it's just identifying that it's a 420a. I've read that misfires could result in this, and that's what I'm hoping. The VE table I had it running on was rough, so I've driven around a bit to try and clean it up. I haven't tried replacing plugs or wires yet, although the plugs are fairly new. Grounds are solid from what I can tell, everything is grounded to the old battery cable (batt has been relocated). The car will run and drive fine with no sync issues when running on tach signal. Shielded wire tapped from the crank sensor.

Any suggestions as to where I should start? I've seen that the version 3 boards have issues, but people seemed to like the 2.2 board better. For those of you out there running 2.2 board and spark, could you tell me how you wired it? The more detail, the better. Did you have this issue? Any remedies you can suggest? I hope to mimic someones setup and go from there.

Many thanks,
Brian