I'm certainly no expert, but I've been fighting off-flavors, too. So far, keeping the fermentation temps down in the mid-60s have produced the best beers I've made. I used a swamp cooler for the last two I made (back in August so it was hot, placed the fermenter in a rubbermaid bin filled with water and rotated in 3 frozen water bottles twice a day). Those beers didn't have the same weird flavor that all of my previous batches had. I'd suggest trying that next time.