[libusb_init() failed err -99 [2013-11-10 04:57:24] libusb_init() failed]

Hey all!

Well I used to have this working some months ago, though it was glitchy at best, and was using a way older version.

GPU: 1x Sapphire Vapor-X 7950
AMD Driver: 13.9
OS: Windows 7 x64
Command Line: cgminer.exe --scrypt -o stratum+tcp://server:port -u user -p pass -I13
(server:port, user, and pass have all been set in the .bat)

On the current 3.7.2, I can't even get the miner to start as I crash with this error instantly upon starting it:
libusb_init() failed err -99 [2013-11-10 04:57:24] libusb_init() failed

I did try an older 3.0.1 build and it crashes as well, no message in the console but the module that crashed is libusb-1.0.dll.  I also tried 2.7.7 which starts correctly but only will mine at around 5khash/s.

I did some searching on google but so far have come up with nothing as to where to even start troubleshooting the libusb crashing issue.  I am not using any USB FPGA/ASIC miners and the only usb devices attached are a keyboard and mouse.

Any thoughts or advice would be greatly appreciated.

Currently just seeing if there is any interest, but I had the idea of selling blocks of time in 1 hour intervals at a set price per hour for mining time on 1 (or more) GPUs (7950s, maybe others).

Would anyone be interested in this?
How much would you be willing to pay per hour per GPU (in USD, I will accept LTC/BTC but it will be converted at the time of purchase to the current exchange price)?

I'm not currently giving out much more detail than this other than it would be automated.  You would provide the pool (or solo pool/client) address you want to mine for along with the worker user/pass.

If there is interest I will begin development and will provide an open beta with very low rates (possibly free) for a short run to test that everything is working and to get user feedback on problems encountered or what to improve/add on.

I'm looking at adding more video cards to my rig, but I am going to be adding them one by one instead of all at once.

Based on price and hashrate for scrypt, I'm thinking the better way to go is 3x7950s (~$960) since I've seen others able to get about 700khash/s with overclocking.  What do you think?

Wish I could post this in the relevant topic but, oh well, maybe someone here has an idea.

I had a few systems available with 3xGTX590s (2 in SLI, 3rd not) but each time I tried to run cgminer it would crash and Windows (7) would ask me if I want to close the application or debug it.  Is there a limited number of GPUs that cgminer can handle on a single instance?  I can run 6 separately using -d0 -d1 etc, but that is annoying and is why I liked this program so much since it was able to automatically run on all GPUs available.

Systems with 2-3 GTX580s (or lower series cards) seem to work fine so far, even with SLI enabled.

If anyone has any suggestions to try I would be grateful.

Would anyone be interested in a VPN service (OpenVPN, SSH Tunnel and possibly PPTP available later) for 1-2BTC/month?

Servers would be located in the Netherlands with 100mbit to 1gbit uplinks. 
No data metering, no logs.


Interested to hear any thoughts, suggestions, etc.