H.264 8K Quicktime playback issue only on M4 MacBooks

Hi all, looking for help and information on an issue I am having.

To preface this, Apple has agreed to buy back my M4 Pro and M4 Max MacBooks, but they have asked me to reach out to Adobe to get more information on this for better understanding of the issue.

I'm experiencing playback issues (very choppy and stutter, skipped frames) on Quicktime (Native Metal) on the M4 chips, but this issue is not replicated at all on the M5 chips we used to test. We used the same exported file to test (Apple support verified the checksums).

Apple has benchmarked the M4 MacBooks and found no technical faults, they have ruled out performance issues on their end. They believe it is a software issue with Adobe and M4 chips, as it works fine on M5.

We use Premiere Pro and Media Encoder for work frequently and have never encountered this issue, only first noticed it a week ago.

Does anyone know who we can talk to get documentation/logs, a sort of paper trail running to talk to Adobe Technical Support, that we can then pass on to Apple?

Cheers.

Hardware:

• M4 Max and M4 Pro MacBook Pro, M5 Max MacBook Pro
• Tahoe 26.5.1
• Premiere Pro and Media Encoder 2026 (updated)

Source:

• Video: 8192x4320 (1.0) | 25 fps | Rec. 709 | Progressive | 00:05:59:09
• Audio: 48000 Hz | Stereo

Output:

• Video: H.264 | 8192x4320 (1.0) | 25 fps | Progressive | Rec. 709 | 203 (75% HLG, 58% PQ) | Software Encoding | 00:05:59:09 | VBR | 2 pass | Target 180.00 Mbps | Max 240.00 Mbps
• Audio: AAC | 320 kbps | 48 kHz | Stereo
• Estimated File Size: 8099 MB