hm2 breaks connection

Hi,
I started with linuxcnc a week ago and want to connect to a mesa 7i96s.
I'm at the stage where everything runs well untill a few lines into the g-code. Then hm2 throws an error for lost packages (I think). A red LED turns on and nothing works anymore. 

I installed a copple different versions of linux.
Isolated some cores
Changed power supply 
Changed IP address to a static one in Geany
My next step is getting a “new” pc. Because I'm using an  18 year old dell at the moment. 

I understand that it is a big learning curve but I am starting to get a bit lost with everything and I need a tip on what I should do next. 

Thank you 

Yes, thas on me

The ping times suggest that you have an Intel Ethernet chip on your
PC but have not disabled IRQ coalescing:

man hm2_eth
 

I would follow PCW's advice but I also see you are running an old pre-release version of linuxcnc.
It is worth upgrading to the 2.9.2 current release.
save your linuxcnc folder and:
sudo apt remove linuxcnc-uspace linuxcnc-uspace_dev
sudo apt update
sudo apt upgrade
Download and run this script to get the latest version of linuxcnc
linuxcnc.org/docs/stable/html/getting-st...th_preempt_rt_kernel

this should also upgrade to Debian 12.4 which should have a later kernel that may also help.

If this breaks, download and install the ISO on the downloads page.

Hi, thank you so much for your help.
I must apologise that I didn't respond quicker but a Cyclone hit us.

I tried to learn as much as possible from your post and I realised that I made some major mistakes. 
And now I decided to start again from the beginning. 

I follow the list from linuxcnc and I have a stupid question. 

 It sais that:
"Synaptic Package Manager search for linux-image and right click on the original non-rt and select Mark for Complete Removal."

 Does this means that i need to remove every file what does not have -rt in it or everything what does not have the version number 6.1.69-1 .?