Hmm, I don't really see a bug, neither in Kernel 3.10 nor in Virtulbox 4.3.2. I mean, I haven't experienced any problem, even after last upgrade of Kernel and / or Virtualbox.
But, I'm using KDE 4.11 (64bit) with Kernel 3.11 (not 3.10) in combination with Virtualbox.4.2.18 before and now 4.3.2.
Maybe there is a problem with Kernel 3.10 in some combination with Virtualbox, but as I've said, I haven't experienced any problem.
Just an idea: Could you consider to install Kernel 3.11?
-Linuxfluesterer (I love KDE ...)
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