Moving CTI by pressing CTRL + arrow creates new keyframes

[Jerry Sky]

I've experienced a really odd issue that I've never come along. When I'm scrubbing through timeline using a mouse, everything is working properly. Unless I move the time indicator by pressing key combination CTRL + arrow right or left. Every movement using this key combination adds a keyframe, but only when a specific property with "Time-vary stopwatch" is selected. If deselected, moving through time is working perfectly.
Probably it's a trivial problem, but I can't solve it. (and I need to say that I'm a newbie to this software) I couldn't find any solution on the Internet or on the Adobe Forums, so I need some help. Thanks in advance.

Tech info:

Version: Adobe After Effects CC (2017) 14.2.1.34

OS: Windows 10 Home; version 1703; Build: 15063.483

PC: Intel Core i5-2400; 8GB RAM; Gigabyte NVIDIA GeForce GTX 760 4GB

[Roei Tzoref]

weird. could be a hardware issue like a keyboard thing or something of the sort. how about using the PgUp/PgDn keys for moving between frame? does it create keyframes then as well?

[Jerry Sky]

Actually, you are probably right. PgUp/PgDn are working without any problems. And that got me thinking, is Synergy Pro (Symless) that I'm running causing the problem? No, at least what I think because I shut down Synergy and even stopped Synergy Service in Windows Task Manager and restarted After Effects. Unfortunately, nothing happens. I have no idea what can cause this...

[Roei Tzoref · Accepted solution]

I suspect it's either a software hijacking the keyboard strokes or a hardware malfunction. PgUp and PgDn are superior shortcut because it's only one key. you only need the Ctrl+right or left if you don't have these function keys like with some laptops or Mac keyboards.

[Jerry Sky]

Okay. So my solution will be just using these PgDn/PgUp keys instead of the 'ctrl+arrow' combination. Thanks for the help!

[Rick Gerard]

Do the values change when you use Shift + Ctrl/Cmnd + right or left arrow? I cannot reproduce this problem using the settings in your screenshot.