I have a new (2015) 255ext and I have intermittent issues with the high frequency start. I could be welding along just fine then when I go to strike and arc nothing happens. I have found if I touch the tungsten to the weld material, without the petal pressed then lift it back up and press the petal it will work every time. It's been like this since new. It does it in both AC and DC, with the pedal and with the finger switch. I've varied the post and pre flow. Brand new tungsten and and clean shiny metal. I've been in touch with Everlast Support and they have already sent me a new control board and HF board. It didn't help. They have agreed to replace the welder, but don't have any right now in stock. I'm just looking to see if anyone else has seen this. I hate to send the welder back if it's going to be the same.