In general, we recommend broadcasting audio in an AAC format, in stereo, at 44100 Hz, and with an audio bit rate of 128 Kbps.
Problems with the sound are usually related to your encoder settings, such as the volume being set too high or the wrong audio input device being selected. For example, if the sound gets distorted during loud parts of your broadcast, first try lowering the volume on your encoder. If that doesn't work then try adjusting the sound before you bring it into your computer. You can use a basic "audio mixer" to be able to control the volume if necessary.
If you have trouble resolving a sound issue, you may want to test the audio cable that you are inputting into the encoder by connecting it directly to a headset or audio speaker to hear the audio itself to ensure audio is working correctly. You can also do a simple audio test by plugging an iPod or similar device directly to the audio input for your encoder system to test and ensure that the encoder is processing audio.
Also, keep in mind that if your computer is older and struggles while broadcasting, then your computer may be a cause of sound issues. If this is the case, then perhaps try closing any unnecessary programs on your computer or try broadcasting from a more powerful computer to see if the problem is still there.