Help with rotation for 9 couples playing mixed doubles on 4 courts

[Jim W]

I have been using the rotation for round robin mixed doubles - 8 couples, 4 courts, where the husbands do not play with their wives and the rotation keeps them from playing against their spouse as well.  We now have 9 couples and need a rotation where a man and a woman sit out each round (not the husband and wife of the same couple sitting out at the same time.)  Any thoughts?

[Ian Wakeling]

I don't think what you ask is possible, as the spouse pairs must sit out together to make a balanced schedule. Here is an example.