New(er) Kernel

[Pete Smout]

Hi,

After updating to new kernel (3.11.0-15) I have been experiencing 
frequent lock-ups / freezes if I reboot to old kernel no probs!
By lock-up I mean complete unresponsiveness from keyboard / mouse on 
GUI, cannot drop to shell (ctrl-alt F1-F6) only solution is hard reboot 
(hold down power button) !!
I have looked in the logs in 'system log' and can see nothing so no-clue 
as to what or why!

is anyone else getting this, should I raise a bug? if so what against 
(kernel update is a tad vague!)

System Specs

Acer Aspire 5720
2.9 gib ram
Intel® Core™2 Duo CPU T5250 @ 1.50GHz × 2
Graphics Intel® 965GM
64 bit system (Ubuntu 13.10 fully updated)

Thanks

regards

Pete S