Injector or coil is the most likely cause. I had the exact symptoms you described on mine, and it was the coil.
The car ran fine, but would misfire under boost, then operate roughly and with reduced power until I shut it off and restarted it. I have I-Drive, so the screen would tell me which cylinder was misfiring.
The simple test is to move the coil to another cylinder, make it throw a code again, and see if the misfire is on the new cylinder.