Speed for 55nm chips should be 1500 and you should have firmware that shows the 55/110nm option so something's horribly wrong with your setup if you're running firmware not designed for it at speeds it doesn't support.
Thanks Mr.Ckolivas, it was very helpfull for me! i was trying 282 and 110nm and connection refused error on the api log, now im running 1400 and 55nm and its mining at 149ghz and 66° celsius because its too hot here in Brazil is summer now... The machine is a Avalon Clone 200Ghz from China, now i will try to reach the 200ghz, you give me da light at the end of tunnel...Thx Ckolivas!
Happy mining for all! 
