My DR-40 is updated to current version 2.50 I plug the USB cable directly into my computer and have tried USB 3.0 and USB 2.0 ports. The USB SELECT screen appears, with BUS POWER and STORAGE options, but it constantly flickers. When I can move the cursor to STORAGE, it momentarily says USB CONNECTED, then flickers again and returns me to the USB SELECT screen. When I select BUS POWER, the screen flickers, but I can see the USB icon over the battery icon during the flickering. The flickering USB SELECT screen usually makes it impossible to control any function of the DR-40 BUT once in a while I can push the >>| button and get to the main screen. There, the USB icon and battery icon keep erratically alternating. Anyone why this is happening?