I sent an email to DA and got a email response as well as a phone call regarding this problem.

This is a problem related to a rich needle setting that usually occurs during idle.
Dave feels it is a product of the small case area. With a rich needle setting, fuel pools in the reed area during idle, then when the motor is bounced or forward motion is stopped, the pooled fuel is introduced into the case. With not a lot of excess room most of it ends up on the piston, at idle this results in the motor dying. In most cases, this goes away once the needles or brought in for the final adjustment.

He also stated they are aware of some needles changing settings at high rpm and are working on addressing that issue.

Also a note on DAs cutomer service. Recently I had to send my older 50 back for some crash damage repair. It was in and out in a two day turn around at what seemed to be a very fair price. Over all I have been very satisfied with the service and the product.