Juddering since December 2020 Update

Platform: Windows 10 (version 20H2)
ISP: BT Broadband
Type of Internet Connection: ADSL
Internet Connection Speed: 70MB
Date & Time: 11/12/2020 @ 2330
Frequency: Always
Character Name: Leara
Race: Hume
World: Sylph
Main Job: DRG lvl 99
Support Job: WHM
Area and Coordinates: Any
Party or Solo: Solo
NPC Name: N/A
Monster Name: N/A
Steps:
1. Approxinately every 30secs to 1 minute, juddering occurs when I run or move (freeze for about 3 seconds then unfreeze back to the action). This has only happened since updating the game yesterday so I thought wait to see if it is my pc. It happened again today so logged off.
2. I then ran "Check Files" through PlayOnline. After 20 minutes, it found 1 file needed repairing so I did.
3. I restarted the game but this hasn't fixed the issue.

I am wondering if anyone else is encountering this issue. If not, should I reinstall the game or does there need to be some emergency maintenance?

Plug a controller in, see if that fixes it. There is a long running bug, if you turn on controller support (or it is auto activated some how) and one isn't there it hitches as you describe.