Problem wake-up from sleep

Hi, I have successfully installed Sonoma on iMac 17,1, so far everything works fluently except for one issue with sleep/wakeup, I’m not sure exactly what could be the root cause but below is what my experience:

1) Bluetooth works flawlessly when after cold start 2) Sleep/wake-up sometimes works, sometimes wake-up takes long time (a couple of minutes), and sometimes doesn’t so I need to hard restart 3) When it takes long time to wake-up the Bluetooth always stops working after waking up. It still shows the devices are connected despite that they’re disconnected and not functional. 4) I also saw distortion of graphics after wake-up which can recovery by itself after 30 seconds (see photo)

I have tried to turn on/off Bluetooth, rest SMC, reset NVRAM nothing helps. What else can I do? Thank you in advance 🙏