This may happen because of an error in sound card driver. To make it simple, you can try reinstalling RadioBOSS to a different folder. This will reset all settings.
Then, in the RadioBOSS settings:
1) in Playback section, set the buffer size to around 40ms (0.04 sec)
2) in Microphone/LineIn section set "Prebuffer" to 0.02 sec and select the correct device/source
You can lower the buffer/prebuf settings until sound becomes corrupted. Doing this you will achieve the minimum latency.
But, it's still recommended to use sound card which supports ASIO API - this will allow to get minimum possible latency.