I have experienced a similar problem. It appears that the audio data in the file is being written correctly, but the metadata that describes the file is wrong. The length is too long and the bit rate is too low.
I have found a work-around. I use Audacity a free download, that ignores the wrong metadata. I load the file into audacity and then just export it back out. Audacity write the file with correct metadata and the problem is solved.