Well, 3.40 (and any other) works for me just fine on PSP-1000 (everything was tested before I posted). I also posted this link on my forum as well, and nobody complained (but nobody tested it on Slim I guess) I'm pretty sure, that it's Slim releted issue.
I think that you should report it in 3.60 M33 bug thread:
https://www.pspx.ru/forum/showthread.php?t=52502