As for your dmesg output, I've only seen that in cases where either the USB port/controller or the USB device/cable were broken. Not saying yours are.
“[...] I should also add that these devices work fine on other distros, so they aren't failing. [...]”
Other distros on that same machine?
JanKusanagi @i at 2015-08-21T16:36:36Z
Other distros on that same machine?”
Yes-- Mint and a few other distros that I tested on this machine were able to handle these devices without any trouble. This is part of why I believe the ports and cables are working correctly. The problem seems to be limited to Mageia only. (Thanks for the response, btw.)