That's surprising, because 205/55 R15s are only modestly low profile. High gearing and low engine noise will leave you hearing tyre noise more than you would otherwise.

First, inspect the tyres for uneven wear because you may have an alignment problem. If you find no uneven wear, try altering the pressures upwards a bit. Tyres generally run at lower pressures in winter because of lower temperatures. It may well be that warmer weather eliminates your complaint by itself by increasing the pressures. If you still have a problem, switch to the Michelin Primacy 3 (but this will be expensive).