I had the same thing happen to one of the plants in the grow I just harvested. It's kind of funny, one of these old posts here said he saw it in a "Hawaiian strain", well, the plant that did it for me was Hawaiian Snow. Some buds 100% amber while some, on the same canopy level, same light exposure, are between 5-50%. Out of curiosity, I tried smoking some of the 100% trichome bud and it was outstanding, zero couchlock effect. Don't buy into the "harvest when milky" "too much amber=couchlock" BS bro-science that keeps getting repeated with no one actually verifying its accuracy...if you harvest with little to no amber, you are harvesting weeks early and greatly losing out on potency, yield, and quality of high. If you want a positive "up" high, get yourself a pure or close to pure sativa AND shoot for 30-50% amber trichomes AND all of the other signs of ripeness. If you want a couchlock strain, do the same for an Indica or Indica dominant strain. The point is, let your plants ripen FULLY and they will display the full genetic potential of their high.