Is that with particularly long tables, or do you also notice it with tables with only a few rows?
Since you mention holding keys and/or typing gibberish, do you have Power Mode enabled (in Settings > Appearance)?
Viewing post in Table Bug
I have some (small) performance improvements coming in the next update that should improve this. It’s nothing huge, but may help on your system.
As a workaround, you can disable automatic table formatting (Settings > Input > Table formatting), and use key shortcuts to manually format tables instead: https://support.deepdwn.com/docs/guide/shortcuts/#tables