high CPU usage

[pasnox]

I have since some times now an issue where my rpi5 fan would spin at 50% (loud noise) instead of 25% (no noise) every 5 or 10 minutes. Initially I thought it was related to the PVR Freebox extension which updates its guide every 5 minutes, but it's not, disabling it still has the issue.
I noticed my fan spinning fast because the RPI reached 60-62° when idling which is weird because to be honest the skin is so simple nobody can imagine that. Then I tested other skins, like the default estuary where the issue disappeared and reached a steady 54-55° when idling and no more issues.
I can't imagine a so simple skin needing so much CPU just to change every 30 secs a background image. Would you mind having a look at this issue?
As of now I returned to estuary because of the permanent noise it triggers, which is very annoying - your skin being so much good!

[pasnox]

I'm using LibreElec 64bits:
LibreELEC:~ # /usr/lib/kodi/kodi.bin --version
Kodi Media Center 21.1 (21.1.0) Git:21.1-Omega
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