Turn signal cancellation issue

[Dallas56]

I took delivery of SPO 2895 a couple of months ago, now have all bugs worked out save one involving turn signal cancellation. The left turn signal cancels perfectly. Approaching a left turn, I engage the left turn signal, it stays on through left turn, then disengages as I straighten up. All good. Approaching a right turn, however, the signal inevitably cancels before I even begin the right turn. It's like a hair pin trigger. You breathe on it, look at it funny, turn the steering wheel the slightest bit right or left, it cancels. That means to give an effective right turn signal to cars behind me, I have to hold the turn signal lever at least until I begin the turn. I can live with this if I have to, but would like to fix it. I have already made the finger, ear, lug adjustment described here: http://www.craigscobras.com/tips/blinker/index.htm

Is this fixable? Is there something I can adjust? Something I can replace?