Yes, I agree, and I said it was the difference between sea and say, but if I wasn't clear, I meant in french
c'est for me is definitely more like 'say', but almost cut short in pronunciation, and I suppose the french sound for c is more like 'si' as the spannish would say it rather than the french.
Complicated I know, but there is a difference.
And I have looked up how to pronounce and listened to 'c' and 'c'est' and there is a difference.
Go to recto/verso dictionnaire and look up them up and further down the page you can listen to them.
I have all too often wondered about how well other posters speak french. I know my own limits, and my poor 'ear' but maybe I am no better or worse than many other posters.