Change IP make much troubles ! How to change IP correctly ?

Raspberry Pi5 + Libreelec 12 on SSD/USB
Files on a SMB NAS

That worked fine during few weeks.
Till 2 days, videos stop every 3 to 15mn :
_ Video freeze during 1-2mn, and then, back to video list.
Or
_ Directly back to video list.

After this stop/freeze :
_ My PuTTY seem work differently.
Nothing go from Libreelec to PuTTY.
Exemple : pastekodi don't show me the link.
_ Send complete logfile don't work.
But send error logfile work.

Few days ago, I only changed IP (by DHCP / MAC)
Then, last day, I rebooted Box, Switchs, NAS to try to solve.
But still don't work.

So many tests, I become crazy

error logfile :
https://paste.libreelec.tv/inspired-boxer.log
Logfiles.zip
http://gooodgame.free.fr/Forum/log-2024-06-01-13.32.55.zip
I rebooted at 15h30
Bugg at 15h31

OMG …
During I write here,
I set the old IP and Kodi is working since 1h …
How to change IP and have Kodi working fine ?
I changed IP by DHCP / MAC address, and IP changed successfully.
I rebooted Box, Switchs, NAS.
Old IP stay somewhere in Libreelec config ?

No, except IP, I did nothing on box setup ... I don't use VLan on my Switchs (just aggregate 2 ports for my NAS)

I really don't understand ... because I do it with all ...

Sure, I forgot something !

I use DHCP from my internet box 192.168.1. (1 to 5) to configure anything (this one took 192.168.1.3)

Then, when it's done, I do MAC address to a fix IP (192.168.1.x not used)

That work all time, that also worked with my Pi4 with Libreelec 11

But unable to change IP on my Pi5 with Libreelec 12

IP change correctly, but Kodi crash after 3 to 15mn, even if I reboot Box, 3 switchs, Pi5

If I remove "MAC adress to another fix IP", Pi5 take 192.168.1.3 and everything is OK in rebooting only Pi5

I thought about IPv6, but it seem deactivated on Pi5/Libreelec

Something changed about network between Libreelec 11 & 12 ? (IPv4/IPv6)

Or maybe something wrong that engage my Loop-Protect on my switchs ?

(expl : Pi5 loop Lan/Wifi ?)(But Wifi deactivated on Pi5 ...)

(I will try to deactivate this Loop-Protect option just to test)