It's a trial and error process. Your ultimate results will depend on which batch you purchased, how cool you're keeping the miner/room, and some luck. To troubleshoot, I always first reboot the miner and keep an eye on it. If it can't hold the freq that it used to be able to handle, then I try to figure out what changed. In all of my similar situations, the change was always the temperature in the room (one time I moved a miner to a hotter location, another time the A/C went out). Once I got the miner back to the same room temperature conditions it was in before, it worked like before. These boxes are a little finicky at the higher freq.