P: ST records and echo of 1sec
A: Make sure SoundTap is correctly set up:
www.nch.com.au/soundtap/support.html#AAA
Try a recoding now.
If the echo remains;
Open WMP and click Tools-> Options
(In WMP 11, this is done by clicking right-clicking on the title bar, navigating down to Options, and bringing up the Options dialog box.)
Click the "devices" tab, select speakers and then properties.
Click the pull down list, and select "direct sound: SoundTap Recorder"