Morning Gentlepeople.

As a coffee newbie I am having some small issues while trying to improve my game. I have a Oracle Touch and subscrube to a local monthly coffee delivery, so my beans change weekly.

My issue is that the grind setting is incredibly different from bean to bean. With my last bag, grind 14 gave a perfect 1:2,5 ratio. With a different bean today, I had to discard two cups before learning that grind size 3 gave me the same ratio. 14 gave me 1:3,5 which tasted rubbish.

The problem is that I got channeling and very little crema.

I guess the questions are: do different beans require completely different ratios or am I doing something very wrong?
Should I accept a very high ratio to avoid channeling on certain beans?
Or should my timer be lower on certain beans?

Thanks in advance for any help and have a great cup this morning!