Changing the boot order?

When I plug usb drives in to my LePotato to use it as a server, I cannot reboot the LePotato witht he usb drive plugged in. I have to remove it first. I’m wondering if the boot order is the issue, because when I don’t have any drives plugged in via USB, it boots normally.

However, I’d like to be able to have it reboot normally with the usb drives plugged in, in the case of a power outage and similar. What way can I ensure that it just boots from SD without some weird boot-loop?

See Attempting to dual boot - #3 by angus