I have several ideas, but most would be rather impractical. The safest way would be to experiment with different versions of USB Loader GX. It could also be because of the system menu IOS, the IOS HBC uses, or the cIOS USB Loader GX uses. If you have changed one of these, this is probably the cause.
If the IOS haven't changed and changing the version of USB Loader GX does not change anything, you might still be able to put some power switch on the cable itself, you know, like some lamps have. But you do need some skill to do this.