We purchased a Frigidaire 30" combo unit with regular/convection oven on the bottom and microwave on top. Our home is extremely quiet but this monster is impossible. Delivered 2/13 and micro souded like a thrashing machine. Four service calls later and noise has improved but with each noise improvement another noise is noticed. Last repair man said it is as good as it can be. DB meter reads at 60 and is horrible - now caused by cooling fan for controls. Store won't budge on exchange or refund. Any suggestions? Is every oven out there this bad?