Try this enable USB debugging from developers menu then power down then hold volume down + home + power. Phone should Boot into recovery. Try plugging in USB and connecting to adb from here in the recovery.
Sent from my LG-VM670 using Android Central Forums
ill give this a try when I get a chance and let you know
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I was meaning try the USB hub if you have one around somewhere. Some phones won't connect on high-speed USB ports all the time so with the hub in-between to slow things down it may work but I'd try to ADB while in recovery first
Sent from my LG-VM670 using Android Central Forums
i do have one, but like i said in OP it did work when i originally bought the phone, but has since ceased
tried hub, no dice