AlexT, can you check repo? After I ran "opkg install --force-reinstall mpg123", I couldn't even find mpg123 on my Edison.
pkg install --force-reinstall mpg123
No packages removed.
Installing mpg123 (1.21.0-r0) to root...
Downloading http://repo.opkg.net/edison/repo/core2-32/mpg123_1.21.0-r0_core2-32.ipk.
Collected errors:
* opkg_conf_parse_file: /etc/opkg/base-feeds.conf:1: Ignoring invalid line: `===/etc/opkg/base-feeds.conf contents below==='
* opkg_conf_parse_file: /etc/opkg/base-feeds.conf:6: Ignoring invalid line: `===end of /etc/opkg/base-feeds.conf contents==='
* opkg_download: Failed to download http://repo.opkg.net/edison/repo/core2-32/mpg123_1.21.0-r0_core2-32.ipk, wget returned 4.
* opkg_install_pkg: Failed to download mpg123. Perhaps you need to run 'opkg update'?
* opkg_install_cmd: Cannot install package mpg123.