CPU cores at 100% despite very few processes using the CPU

On my system htop is constantly showing 100% load on four out of the eight logical cores on my system (system specs below). The issue is that it's a freshly installed Ubuntu Server 22.04 and there are very few processes running, and htop is not showing any significant CPU load on any process. If anyone has an idea where this could come from or what to look for it would be very helpful. Some observations: - The problematic cores are all in blue which indicates it comes from low priority processes. This stays stable at exactly 100% right from boot and never goes below. - Searching for similar issues it's often times about kworker running hot, which is due to hardware interrupts. However this does not seem to be my issue. When I run grep . -r /sys/firmware/acpi/interrupts/ it shows 0 on all interrupts and when showing kernel processes in htop (shift-k) it does not indicate high cpu usage from kworker or anything else. Version: Ubuntu 22.04.4 LTS CPU: Intel(R) Core(TM) i7-6700K CPU @ 4.00GHz Thread(s) per core: 2 Core(s) per socket: 4