Once my Antminer U3 has been running for a bit, it gets this about every 10 seconds:

 

 [2015-09-03 18:09:24] AU3 1: No valid hashes for over 2 secs, attempting to reset
 [2015-09-03 18:09:24] AU3 1 attempted reset got err:(0) LIBUSB_SUCCESS
 [2015-09-03 18:09:24] AU3 1: No valid hashes for over 2 secs, attempting to reset                    
 [2015-09-03 18:09:24] AU3 1 attempted reset got err:(0) LIBUSB_SUCCESS 

Despite this, the hashrate manages to stay around 60 - (about 5Gh/s worth of old erupters and antminers), dipping briefly after each reset.  Is it possible that the AU3 is simply getting hot and taking a break?  Is there something I should tune to make it work a little less hard (and reduce the log file entries)?  I am using all defaults.  I see people are tuning voltage and freq.