Below is the best 10 round schedule I can find. There are probably many ways of adapting to 4 groups of 2 rounds. For example leave out rounds 1 and 2, and swap around rounds 8 and 9 to avoid the back-to-back byes for teams 8 and 10. Hope that helps.
( 8 7 2 v 14 6 9) (11 4 10 v 13 5 15) ( 1 12 3)
( 9 8 3 v 15 7 10) (12 5 6 v 14 1 11) ( 2 13 4)
(10 9 4 v 11 8 6) (13 1 7 v 15 2 12) ( 3 14 5)
( 6 10 5 v 12 9 7) (14 2 8 v 11 3 13) ( 4 15 1)
( 7 6 1 v 13 10 8) (15 3 9 v 12 4 14) ( 5 11 2)
( 2 3 1 v 11 5 9) (12 8 10 v 13 14 4) ( 6 7 15)
( 3 4 2 v 12 1 10) (13 9 6 v 14 15 5) ( 7 8 11)
( 4 5 3 v 13 2 6) (14 10 7 v 15 11 1) ( 8 9 12)
( 5 1 4 v 14 3 7) (15 6 8 v 11 12 2) ( 9 10 13)
( 1 2 5 v 15 4 8) (11 7 9 v 12 13 3) (10 6 14)