In Kugou Music, you can adjust the speed of a single song through the following steps:

1. Open Kugou Music and select the song whose speed needs to be adjusted.

2. Play the song, and then click the "Change Speed" button at the bottom of the interface. If you don't find this button, you can also set it through the "speed change" option in the right-click menu.

3. In the pop-up "Variable Speed ??Playback" window, you can see the current playback speed and pitch information. If you only want to adjust the tempo without changing the pitch, you need to turn off the "Pitch Shift" option.

4. Adjust the speed: Adjust the speed by dragging the progress bar or manually entering the value. Note that the adjustment range should not be too large, otherwise it will affect the listening experience.

5. Click the "Apply" button: After confirming the adjustments, click the "Apply" button to save the settings and take effect.