Hi Sp00n1980,
I have an equal problem with my Ant. It hashed up to 2.1ghs/s then started to slow down. After restarting it, it never recovered and now I can get it only to 540mh/s but stable with no error. Before with 2.1ghs the error rate was below 1% until it slowed down (still not more HW errors). Between I tried a lot of stuff, frequency settings, CPU cooler directly attached, 2.5A PSU but still its slow...will try to figure out what went wrong if I find some time next week.
Greetings,
miniasic.