CLK320 noisy fuel hose!

[HarryM]

2001 CLK320 118400 miles

I replaced the fuel filter and now one of the fuel hoses is making a loud humming sound. The filter (part no 002.477.30.01) has four hose connections. The large diameter (10mm) hose from the tank to the center of the filter is vibrating under tremendous pressure. If I pinch the hose, the noise stops. It sounds as if there is air trapped in the hose somehow. I drove the car a couple of miles hoping the noise would go away, but it didn't.

What crime did I do to deserve this?

Why is his hose under pressure? If it's coming from the tank, shouldn't it be under atmospheric pressure?

In case it makes a difference, the filter is Meyle.