Were you able to do the multimeter ohm check to see if the drain to drain short was present? I can't recall where I saw it discussed but that short between drains was initially fairly common, it seems. I think Hans shifted component location a few thousandths away in subsequent productions....
Meanwhile, some old stock may be sifting through.
Hey! I used the wrong assembly revision and built a totally deaf QMX!
73
Karl
KI4ZUQ
Karl