Moved to User Support Hub that is more appropriate for community support.
No. The differential should be 7.8 psi max at that altitdude.
8.35 psi is the max above FL370.
FYI, I just checked mine at FL290. Once the cabin stopped climbing, the diff was 7.8 psi and the cabin altitude was 4,500.
When starting the level off, the cabin was at about 4,000 and climbing 3 or 400 ft/min., I saw the diff as high as 8.1 so still not as high as in your picture.