u/Big_Web6334

Hi everyone, I got my new machine a couple weeks ago as un upgrade from my Nespresso. I have been using Rave (UK) coffee beans. I usually make lattes. The espresso has a very sour after taste. I have tried a finer grind, increased the temperature. The only thing that worked was moving the bean strength to low instead of medium. This got rid of the sourness but now obviously the espresso taste is quite light. Is there anything else I can try?