[Artie Medvedev]

I’ve had the same issue with 4-channel recording recovery. At first I’d tried to recover wav files with Recuva software. Stereo mode recordings recovered well, but the 4ch files were suffering from the noted “echo effect”. Than I’d tried various methods and “Stellar Phoenix Windows Data Recovery” (v6.0 technical edition) software did a good job. It recovered 4ch files in a right way with an Advanced Scan in a FAT mode. So try it.