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owl
10 minutes of head unit shouldn't drain the battery completely, it might have been low already.
If it is that power hungry and it's drawing power while the leads are on, then it's likely it won't jump.
If you've got time and want to go through this methodically, disconnect the head unit then try jumping it again to either rule out the head unit or identify it as the problem.
If you remove the head unit and it still won't jump then plug it into a battery conditioner to check the health status of the battery.