Update your post to include full system hardware specs and OS information.
Take a look in Task Manager and Resource Monitor: How many apps are running that are making use of the host pc's audio hardware and software?
Try using such apps but only one at time. Disable all except one in Task Manager > Start up. Or prevent any of them from launching at startup.
Just click to open and run any given app when desired or required.
Determine if the delay is present. If not then launch another app that uses audio.
Determine if the delay re-appears. Make take some trial and error to test various app combinations.
If you discover some app combination that causes the input latency then that will narrow down the possible culprits.