Quiet inside 205/55 tyres for current model car?

[sonneur]

My current model diesel multispace car does everything I need, except for road rumble on bad surfaces (it's OK on good ones). It's got newish 205/55 x 17 Michelin Primacies (on alloys), which have a good 'noise outside' rating, but they can rumble inside as loudly as the worn EfficentGrips I replaced. I've had sound dreadening pads fitted to all areas of the body - that helps, but not enough. I guess one answer is to fit 16" steel wheels with higher profile tyres, but short of that, any suggestions - do any of the new 'quiet technology' tyres come in this size? Thanks, Max