Voicemail ==> E-mail Problem

Several of my extensions forward the WAV files to e-mail. Sixty percent (but not one hundred percent) of them come through corrupted. The attachment shows up as hex in the text. The HTML shows up as codes in the e-mails. I’m using a pretty standard PBIAF (FreePBX version 2.5.1.5) configuration. It is less than two weeks old and there are no custom scripts. Other than changing the default e-mail address in. My voicemail module is 2.5.1.6 Any clues what to look at?