Low pressure from Mira sprint

We have just moved into a house with a Mira 7.5kw electric shower (mains fed, first floor). The pressure is very low, whether you run it at burning hot or freezing cold. I have replaced the head and the hose but if anything the problem has gotten worse. We have only lived here one month so don\\\'t know if the problem has gotten worse over time. Pressure from the bathroom cold tap is excellent. Would getting a higher kw shower do me any good or does it sound like a blockage/shower is knackered?

Please help - I am starting to smell!

Are you sure the bathroom cold tap is off the mains and not from a cold water storage cistern?

Are you sure the shower is connected to the mains and not fed from a cistern?

If they are both off the mains it could be that the bathroom tap has a good water flow rate but not necessarily a good pressure - there is a difference.

You really need to find out what the water pressure is (dynamic - with another tap running at the same time).