Yes u can have all audio equipment insued through your vehicle insurance I carry full overage with comprehensive I have every purchase recorded with my provider be advised that u MUST KEEP ALL RECIEPTS, but non the less it is all insured I pay mabey 30 more a year now but its worth it if it gets jacked im coverd and I sleep better at night. Here is exactly what my insurance statement states about it.
In cosideration of theft , physicle damge, premium paid on the vehicle shown above, it is agreed that the policy is amended to afford insurance for direct and accidental LOSS of, or DAMAGE to items listed below.(IE-- YOUR SYSTEM)
Our limit of liability will not exceed the lesser of the Actual cash value of these items listed or the Actual cash value of the vehicle..
So u see not only am I covered from lame ass punk audio jackers, am also covered if my **** gets damaged all the way down to my ipod , so it is a fact can and should insure your system, its worth it