2JZ GET knock problem

I recently brought my car to get tuned. They had no issues on the dyno. Driving at low RPM on transition to boost it picks up knock. It only happens between 90 to 110 kpa between 2000 to 2400 rpm. It is running between 22.5 and 25.5 degrees timing. I pulled a half degree and it still happens. I brought it back to the tuner he said to adjust the sensitivity of the knock sensor. This is his first JZ. Any Ideas?

1/2 degree of timing is nothing. Try 3 or 4 degrees in that area and see if you still see the knock. If that doesn't fix it, then it may be false knock and adjusting the sensitivity or knock threshold in that area may be required.