CPU usage spikes to 100% then returns back to normal when task manager is opened

I've tried scanning with MBAM incase it was a bitcoin miner (i followed this guide https://forums.malwarebytes.com/topic/241749-cpu-usage-high-until-i-open-task-manager/).

I haven't downloaded anything recently so idk what program could be the cause of it (if it is a bitcoin miner).