DsoundScope.dll is a backend library for miniscope v4 making use of sound card (via a DirectSound interface) as a data source for PC oscilloscope.

Sound card DirectSound PC oscilloscope

Sound card as oscilloscope has some positives:

... and severe drawbacks:

If you feel comfortable with soldering iron chances are you can modify your sound card to allow DC component measuring - see description how to modify SC-5500P USB sound card from Trust. Another modification suggestion can be found at http://www.qsl.net/om3cph/sb/dcwithsb.htm page.

Popular cheap USB sound card (probably poor choice for a oscilloscope): C-Media.

Another USB sound card variation (same chip probably but looks like better choice) C-Media 2.

And now for something completely different: dsoundscope.dll source code + binary:

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