Based on content by William Walsh (original HERE).
Here is a ZIP file containing three MPG123 for AIX binaries. This file is self-extracting on an RS/6000. As per the original e-mail, these are the functions of each file contained within:
mpg123-com works on every machine, but not optimal performance
mpg123-pwr for POWER machines like 7012-3xx or 5xx
mpg123-ppc for PowerPC 60x like 250/41T/42T/C10/C20/43P
There is also a Win32 version contained in this ZIP file:
Please don't contact me for support or assistance in using these files. I am hosting them as a courtesy to Uli Link, whom you may contact on the comp.sys.ibm.ps2.hardware newsgroup.