A modified version of the 4chan Sound Player which supports masked files is available here. They should also work with the new player by dnsev.
You can convert sound images as you upload them, and create sound images from Ogg files, with this userscript. For other types of appended data, use this.
If this method becomes blocked, try using dnsev's format using LSB-based steganography. The on-upload converter also works with the stego format.
Remember to always keep a copy of the original version when you use a converter like this!
Note: Recently (January 19), an innumerate 4chan developer added new file size limits which blocked large images whether or not they contained embedded sounds/files. These limits appear to have been removed now.