Bad echo when recording an online radio station podcast

I’m trying to record on a Windows 10 Pro, hi-spec PC, using Audacity 2.4.2.
I want to record a radio podcast using Audacity, without using an external microphone; but I get a very strong, increasing echo that obliterates the original message after a few seconds.
It seems that the recording picks up its own audio output after a very short delay, and adds that to the incoming recording. Hence it gets an increasing echo.
I have tried all combinations of the drop-downs: Audio Host, Recording device, and Playback device. I get minor variations in the bad echo, or complete silence, no recording.
There must be a way to do this!

Turn-OFF [u]Software Playthrough[/u]. It creates an internal feedback loop when recording streaming/internal audio.