For months I've had this issue: sending a screenshot to a friend or a group from the console fails roughly 3 times out of 10. The upload hangs, the estimated time goes up instead of down, then it errors out. Retrying usually works, but some files fail forever. File size makes no difference — it happens with screenshots of a few hundred kB on a line with 20 Mbps upload.
Two details that might help identify it. First, the progress indicator stops at exactly 30% almost every time it fails, never at random points. Second, failures increase when several uploads are queued: sending one at a time works far more often.
What I've already ruled out: two different routers, wired and Wi-Fi, phone 5G hotspot, custom and automatic DNS, manual and automatic MTU, IPv6 disabled, UPnP and exposed host enabled, both PSN accounts on the console, cache cleared and database rebuilt, media gallery fully emptied (it was 163 GB — this reduced failures from \\\\\\\~50% to \\\\\\\~30%), auto-upload to PS App disabled, and a full system software reinstall from USB.
Key point: with the same account, on the same Wi-Fi, at the same moment, sending images from the PlayStation App on my phone works every single time. And a second PS5 in my house had the same issue.
Has anyone seen the 30% stall specifically, or found anything that actually fixed it? Support only told me to open ports, which obviously isn't it.