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Install the drivers provided with your hardware before running the TVR 2.5 setup.

This is often caused by incorrect audio input settings. Ensure the audio cables are connected to the USB device or your PC's "Line In" port, and that the software is configured to use that specific audio device. Honestech TVR 2.5: TimeShift Limitations | PDF - Scribd

Before performing a serial update on the Honestech TVR 25: