[PROBLEM] Some probs with Xbian on RPi4

[Don Pedro]

Hello!
I'm experiencing several severe problems with xbian.
Hardware: Rasberry4 with 4 gigs of RAM, PVR backend tvheadend hosted on a Debian Bullseye machine.
Namely:

• Blank screen/no video output:
  Every now and then (mostly when the system is currently unused and the TV is off, couldn't figure it out more closely) video output gets lost, the TV just states "No signal". At this time a login via SSH and a reboot command is possible without a problem (and it's fast as always). Kodi is still running according to htop. When the reboot is done video output is restored.
• Severe network problem:
  Very seldom (but too often to be dismissed as a glitch) the NIC goes berserk (meant literally)! It constantly and at a very high rate emits packets. The rate is so high that the Raspi cannot be reached via SSH. In fact it is chocking the whole network it is connected to, even the router is not able to answer DHCP-requests, clients will not get an IP-address! There's nothing else to do a hard reboot (AKA power cycle the raspi) to return to an operable state! So far I can only judge by the flickering LEDs on the switch that the Raspi is flooding the network, I wasn't able to wireshark the packets, I was glad that a reboot reactivated my network!
• Kodi experiencing delays:
  Kodi is having a lag every now and then, most often when freshly started, IMHO not suitable for a Raspi4 having a large amount of RAM. Partly the lag is several seconds long, up to minutes(!!). During that time I'm able to SSH it and htop shows neither a high CPU load nor a high RAM usage.
• Disappearing EPG:
  It happened now the second time that after a power failure the content of the EPG is all empty! When this happens watching a TV-station for some time or purging the EPG-database (using the GUI entry) on the Raspi this doesn't change a thing (while Kodi claims for the menu entry that it will reload the EPG from the PVR-server). The first time - if I remember correctly - the EPG filled over a long time (many days), station by station. Strangely I can log in to tvheadend via the web interface and I can see all the EPG data present on the server! I can also use it to program recordings on the server and it's working. I don't believe it's the PVR-Server, it's really rock solid! It's on a Linux machine running Debian Bullseye and it never crashed or did anything bad.
  

So, WTF? How to find the reason behind those effects? Someone any idea?

BR

Don