Comment 1 for bug 581704

This is probably a udev issue, not a xkeyboard-config issue.

Normally you edit the relevant files in /lib/udev/keymaps/hewlett-packard* and you specify what key is which.
When these key work sometimes and other times they don't, then it's strange.
You can get debug information from /var/log/Xorg.0.log and ~/.xsession-errors which you can post here.
See https://wiki.ubuntu.com/Hotkeys/Troubleshooting for more on configuring the hotkeys.
These issues would normally be reported to bugzilla.kernel.org, under the udev package.

I'll mark the xkeyboard-config part of this report as 'Invalid'.