Saw this thread and I know it's old but found sure fire way to correct any and all A/T issues with the mvp's. simple solution is to remove trigger and drill and tap it for a 6-32 set screw. Set trigger pull by adj set screw. 100% guarantee to fix issue.
Reason- if trigger back all the way first shot in a/t works but rest fail. But if you bring the trigger just hair forward it will engage and shoot. By installing set screw you make the trigger come back to the sweet spot.
And yes the sear set screw describe on other page was tightened a way in but still had at issues.