Gday BennyB and welcome to the forum.
The easiest (not cheapest) solution to your problem is to buy yourself a decent grinder.Hi all. *Ive had my Imat Mokita for about a week but have experienced some trouble with pre-ground coffee (I dont have a grinder).
Youll find it very hard, if not impossible, to get the consistency you need for good espresso from pre-ground coffee bought from a shop. There are variations in every grinder, even between different shops with the same name, variations in humidity and the age of the beans. *All of these factors will impact on the grind which will impact on the final product.
Without getting into in depth discussions about the relative merits of various coffee suppliers, the grind supplied to you by this shop may have suited to their coffee machine, not yours, due to above mentioned variations.My question is this, why do coffee shops grind so course for espresso makers?
Again, the best solution is to buy a grinder.
Hope this helps,