dude when ppl say that u can use -1 or 10, they mean that -1 is otserv default and 10 is 10%
u can use any number between 0-100.
100 = 100% loss
50 = 50% loss
10 = 10% loss
5 = 5% loss
Try to reduce from 10 to 9, 8, 7, 6, 5, 4, 3, 2, or 1. And see what is the best loss for u.