I have a Lenovo x220 tablet running BT5 R2 (GNOME if that matters). This issue isn't huge but it has me curious as to what is causing it. About 1/3 times I boot BT5, the keyboard stops responding at the login prompt. It functions fine when picking boot options in GRUB, but then the entire keyboard (not just letters/enter) stops working after that. Hard reset and another attempt usually fixes it, but not every time. Does anyone have an idea where to look first? I'm at a loss since I can't even do any diagnostics when it happens, and when it doesn't happen there's no trace of a problem.