Just take the signal and ground from your transmitter and input it on the audio (mike) input of your PC. You can use a shielded cable or two SHORT pieces of wire.

Download RCAudio.exe here:
Channel 1 is on top, left is left...
For transmitter connections please refer to
If you need more diagnostics, please refer to (in this forum):
Errors and problems => Windows version => Diagnostic tools...
Phil.