I recently completed building my t-Rex pro 3gx heli. After I installed the batteries I tried to test out the motor to ensure it spins the correct direction. My issue is I do not get the low throttle arming sound. The motor will not engage. I have tried setting the low throttle end points to 120%, set trim all the way down. Nothing. I do get the 12 beeps when the bats are plugged in. I even tried to get into the programming but I can't even get into that . I tested the 3gx throttle port by plugging in a servo and it does work. Has anyone ever had an issue like this before?

my radio is the spectrum 7s

Troy