intermittant 3rd brake light?

[rdass623]

on my 05 boxster, recently my 3rd brake light has been intermittent. I have removed it and found it is a non serviceable led bar. it appears the connection to the light bar is in good working condition (no corrosion or frayed wires). the rear lower brake lights are functioning properly. but the warning message keeps appearing on my dash display for the onboard computer. while stuck in traffic, I noticed the third brake light going on and off in the rearview mirror from a reflection in the bumper of a truck behind me. so I have a confirmation this is a light problem and not a computer glitch. I was wondering if someone has had a similar problem and what their solution was. I don't think it is the brake switch, because the brake lights in the tail light assemblies are not intermittent. any ideas, or is this a replace the 3rd brake light bar?

thanks in advance for any suggestions