"sh can't access tty: job control turned off" when i plug in the Unicorn hat

Hello, I am new to the raspberry pi community and have a raspberry pi B+.
I love to be able to program some light shows with the Unicorn hat but I came to a snag.
Both the raspberry pi and the Unicorn hat are brand new so after the initial unpacking of the OS, i powered it down plugged in the unicorn hat and powered it back on. At boot up i got this line
"sh can't access tty: job control turned off". At first i thought it was the pi acting up so tried it several more times. Finally i unplugged the Unicorn hat and the pi started to boot up.
I have searched the web but couldn't find an answer to this problem. Any assistance would be appreciated.