Last week a video appeared on the Web from David Lee showing how the new MacBook Pro would throttle down speeds when it got hot under processor loads. Apple told me that the issue Lee was experiencing has been identified and is being fixed today.

As you can imagine, when Apple heard about the problem, they contacted Lee and worked with him to isolate what could be causing the thermal throttling. After extensive testing, they did find the issue, and luckily it wasn’t a hardware issue, but rather a software bug in the firmware.

“Following extensive performance testing under numerous workloads, we’ve identified that there is a missing digital key in the firmware that impacts the thermal management system and could drive clock speeds down under heavy thermal loads on the new MacBook Pro,” An Apple representative told me. “A bug fix is included in today’s macOS High Sierra 10.13.6 Supplemental Update and is recommended. We apologize to any customer who has experienced less than optimal performance on their new systems. Customers can expect the new 15-inch MacBook Pro to be up to 70% faster, and the 13-inch MacBook Pro with Touch Bar to be up to 2X faster, as shown in the performance results on our website.”

The bug affects the Core i9, Core i7, and the 13-inch models, so you should install the supplemental update when it comes out this morning.

As Apple said in its statement, all of the performance benchmarks on its website are accurate. The company said that you needed the right combination of workloads for the bug to manifest itself and in all of their testing, they never encountered the problem.

In fact, many people using the MacBook Pro probably wouldn’t have seen the bug manifest itself at all because they didn’t have that perfect storm of extended heavy workloads to make it happen.

As it turns out, the fix for this is straightforward and can be applied to all users very quickly.