The USB port(s) and/or hub(s) on the computer may not supply enough power to charge the DS-4000’s batteries and operate the recorder. Try turning off the USB CHARG. option in the SUB MENU. This may make it possible for the computer to connect to and power the DS-4000 because no power will be diverted to the task of charging the recorder’s batteries.
Some computers running Windows XP Professional or Windows XP Home Edition may not initially be able to connect to the DS-4000 using the bundled USB cable. The computer’s USB settings need to be changed. Refer to the DSS Player software’s online Help for instructions.
Verification Source: Olympus Website