How long have you been playing it? Is it your first metal piece? Often when you change pieces your eoumbechure is going to to a whole bunch of change to conform to the new peice; wether it be dropping your jaw, bringing in your corners, whatever. Just give it some more time. You should really try a piece before you buy it.

Is the mouthpiece new off the shelf? It is possible the rails and tip aren't level left to right. Play the mouthpiece to the left and right sides of your mouth to see if it makes any diference. If it does, that might help diagnose the problem. It is also possible the table curve is flattened leading up to the tip if someone worked on it previously and didn;t know what they were doing. I had to spend a couple hours with a brand new Dukoff to take care of the poor finishing of the reed surface. I would expect Meyer to be doing a better job considering the brand reputation, but who knows. Maybe they're looknig to save a buck as well... I'll use a Bari plastic reed as a convenient window to measure-adjust-measure for good contact when I'm adjusting my mouthpieces. A stiffer reed may help, too, but even a reed as soft as 2 1/2 shouldn't squeak unless it's a bum reed. If the problem is really the mouthpiece, a stiffer reed will help cover up the problem but not solve it. A poor sealing mouthpiece won't play as clearly, either. Good luck.