The purpose of this little sine wave generator is to generate a clear sine wave on both channels that will be phase locked. So you can measure the phase shifts between different frequencies on your soundcard. But of course you can use it for many other purposes.
One of the biggest advantages of Little SineGen is that it can process at any sampling rate your soundcard can handle. To use Little SineGen just select your soundcard. Set the sample rate. You can also try the extended options, this gives you the possibility to test other channels on your soundcard and generating 32 bit sine waves. Click on start. Now you will hear two sine waves. The left channel generates the frequency you selected, the right channel is a division of the left channel frequency. You can select this division. The maximum frequency it can generate is the sample rate frequency divided by 2. If you select "Swap frequency" then the left and right channel frequency will be swapped. Only the frequency will be swapped not the volume and phase shift. Be aware that any change in the setting can take up to 2 seconds before it apply.