Extruder stepper stops and starts (SOLVED)

[2minutedrill]

I can't figure this one out. Rostock max V2 biuld kit from approx 7/16. Machine has been running great except a small endstop hiccup about a month ago. New endstop and printing for several weeks, no problem. All of a sudden, the extruder motor randomly stops and starts.
Troubleshoot so far.
From Mattercontrol try to extrude 100mm of filament (even with no filament) stepper stops and starts several times(stalls).
Repetier 0915
Mega 2560
motherboard 301

Extruder motor will run (stalls) with or without any heat applied to extruder nozzle.
Motor is ok, exchanged a tower motor and motor behaves proper.
Reprogrammed Rambo 1.3v extruder E0 to E1.
Changed current in config file from 140,140,140,130,0 to 140, 140, 140,0, 140.
wiring passes connectivity tests.
Extruder nozzle will heat, xyz home fine, heated bed will heat.
no effect using above changes.

Again,nothing new was added and had been running fine. Started a few layers into a repeat of a part that printed fine.

Thanks in advance for any suggestions.

[2minutedrill]

Here's a quick video of problem. No filament, ) 0 degrees tmp set on extruder. neither way makes a difference. eeprom cleared, loaded know good one.

https://youtu.be/WSKMrZYugYU

trying to extrude 100mm thru mattercontrol 1.61. Not skipping (??) just pausing then starting.

[2minutedrill]

OMG!!!!! It was Mattercontrol 1.6 and my old ass computer (64bit win7 athlonx2)usb not able to send data fast enough but 1.53 works fine. Damn there goes 1 week i'll never get back.