Let me see if I can get this right.

4 4
4 4
4 4
4 4
4 4
4 4

So there are only 6 possible combos. If there were 5 suits:

4X 4
4X 4
4X 4
4X 4
4 4
4 4
4 4
4 4
4 4
4 4

There would be 10 combos.

i.e. if there are four suits, number of possible pairs is 3+2+1, and so on.