TB123, I found trim 1 did that to me ( I first thought the trims were screws!) Try it a little to the left, or a little at a time until you have it. After adjusting trim 8 ( a bit to the right) the mod is great-useable and musical. With regards to the EH tech guy, could you provide us with what each trim does? Mine sounds good but I bet I could dial it in even better because EH just cant afford to spend too much time on each one. That hissing is not make or break, but maybe could be improved- the carbon copy is way quieter, but not as musical or as fun as the MB.