Windows 8/8.1/10 Odd stutter that happens every 5-10 seconds

Convinced my partner to switch to MapleLegends, however, she has these odd half-second stutters that happen every 5-10 seconds.

I defragmented all her drives (fresh installed ML to SSD).
Adjusted config file accordingly.
Turned down graphics.
Tried to see if it was caused by any USB devices (even with all plugged out the error continued).
Ran as admin.

I remember that there used to be this issue where the game was looking for a controller to be connected and you had to plug a random controller with a relevant program for the stutters to disappear but here this doesn't seem to be an issue.

If there's anything else that I could do to get those stutters to disappear, then please advise me accordingly.