RM File Extension

RealMedia is a multimedia container format created by RealNetworks. Its extension is ".rm". It is typically used in conjunction with RealVideo and RealAudio and is popular for streaming content over the internet.

WAV File Extension

Waveform
File extension: .wav
MIME type: audio/wav
audio/wave
audio/x-wav
Type code: WAVE
Uniform Type Identifier: com.microsoft.waveform-​audio
Developed by: Microsoft & IBM
Type of format: audio file
Extended from: RIFF

Extract audio from RM to WAV with Mini-stream Ripper