Determine computer audio device. Determine computer audio device. In XP, go to Control Panel – Sounds & Audio Devices – Audio Make note of the Default Device for both Playback and Recording.
Determine Sample Rate In Fldigi, go to Configure – Sound Card – Settings. In the Sample Rate window (upper) check the values for Capture and Playback. If the box shows Native click on the box and find the numerical value. Make note of the sample rates for both Capture and Playback (the values are probably the same).
Open Check SR program. Select the correct devices for Input (Recording) and Output (Playback). This is the info you found in step #1.
Select Sample Rate Enter the sample rate value found in step #2.
Start Sound Card SR. While the program runs you will see changing values displayed in the Sample Rate and Difference windows. The values will begin to stabilize after several minutes. You should have values you can use for correction after 3 to 5 minutes.
Enter the Corrections. Open Fldigi, navigate to Configure – Sound Card – Settings. Enter the corrections in the boxes in the corrections area – Input value in the RX box, Output in the TX box.