I have a Delonghi EC750i, manual espresso maker. Its worked very well for about 7 months but lately Ive had a problem with the coffee flow. The first cup is fine, but for the second and subsequent cups the flow is irregular and the coffee comes out frothy. The taste appears to be unchanged, but the crema, usually thick and velvety is disturbingly frothy. I maintain the machine well always use filtered water and descale regularly. I took it in for "repair", but this hasnt helped.