i got my erupters connected to my pi and its running just fine. 
i guess i am confused as to what you are saying.??
i guess i am confused as to what you are saying.??You will never get back your roi unless you bought them super cheap
roi roi ROI roi thats all ya talk about... its a hobby not a freaking business.
and besides if you must know i have made roi already about daily to every other day.. paid cash for it. not bitcoin.
I think the "hobby" boat sailed away about a year ago. Its now a monsterous runaway freight train fueled by greed and millions of dollars.
If i wanted to mine and lose money for "hobby" purposes, I would just CPU/GPU mine.