Slows down, have to reboot and then its more responsive.

[mahesh]

Ubuntu 20.04.3 is very responsive but seems to slow down after I have used apps like Virtual Box or left a YouTube video open.
Even though I close those apps, Ubuntu remains slow until I reboot.
Its like something is continuing to consume resources slowing the OS down.

Any ideas?
How would one trouble shoot a situation like this?
Carl
My other hobby is antique Radios and TV restoration.