News: Latest stable version of Bitcoin Core: 0. I disconnect all and then only connect those one that did not work, then they work fine. I need another group of usb port? Advertised sites are not gridseed mining rig bitcoin by the Bitcoin Forum.
They may be unsafe, untrustworthy, or illegal in your jurisdiction. If you are using a shared USB hub or port, you will have power issues. The hub can only supply about 500mA. USB communication circuitry might be getting power from the USB hub instead of the device power. You may consider using separate hubs or ports, or at least using powered hubs.