Slow startup and cleaning performance

Hey there,

After installing CCleaner Pro on my new PC I've noticed a large increase in the program's startup time after the PC has been running for a while. Rebooting makes CCleaner run instantly again. This also applies for the cleaning process itself, which changes from nearly instant to almost 10 seconds.

Smart cleaning is turned on, CCleaner is installed with the standard settings on an M.2 SSD on Win 10 home.

Any idea what's causing this?

Thanks in advance.