I have a Tecsun PL-600 and when I can receive clear signals, and they come through just fine on headphones, and through the speaker. If I'm trying to receive RTTY or fax, when I connect the radio to my computer the signal becomes inaudible because a huge amount of interference comes through. It only happens when connecting the radio to the computer, so I assume it's something to do with interference going into the radio through the audio cable. But I have no clue if that's even possible.
Is there any way to stop the interference that happens and what is causing it?
Here's a signal recorded with my phones microphone, using the radio's speaker. The signal is coming through very loud and clear. Here's when I have the radio plugged into the computer and I used the computer to record the audio directly through the input. Be warned that both the audio clips are quite loud, especially the one with the noise.