Help! carp slave take over as master at boot!

[Motty Cruz]

Hello, I have two machines running FreeBSD 10.1 Release. Machine A is 
the master in Carp with advskew 20 and Machine B slave with advskew 200 
both are set to advbase 10. however, slave machine becomes Master on boot;

my questions is, how do I configure both machines so if reboot any of 
the machines whatever machine is Master stays master if secondary 
machine reboot.

Thanks,