bfgminer will find and start all four miners, but almost immediately will start throwing HW error "Error: Get temp returned empty string" for all but the first miner found. bfgminer runs normally if I plug the miners into 4 of the PC's 2.0 and 3.0 USB ports. Suggestions?
The original problem was that BFL14 (always #14) was giving the 'Error: Get temp returned empty string". Not immediately, but once it started (typically after a few minutes or hours) it would not recover until bfgminer was restarted.
Now, even with the swapped PC (and OS change from Win7/64 to Win7/32), swapped USB hubs, *and* swapped Singles (I swapped BFL14 for a 'known good' Single from a different cluster), I'm still getting the same error message. The interesting part is that it is being reported on the 'new' BFL14!
Since I replaced basically *everything* and the error did not go away, there's not much else I can do with this cluster. I've since reduced it down to 14 Singles and haven't encountered the error since; the Single I removed is mining elsewhere, and it hasn't had a problem either. Perhaps there is an issue with 15+ USB devices? I suspect this is not a common configuration so it probably does not get a lot of testing.
For now I have a workaround so I'm not particularly concerned. I'm more concerned about the general instability of bfgminer versions higher than 2.9.9 on my systems. I may as well ask: Does anyone else have a 15+ cluster of Singles running on a single instance of bfgminer? If so, what version are you running and what are your experiences?