Have you done something funky with your menu display settings? When the option is on, the icon at the beginning of the menu title should look like it's inset in a carved out square. When it's off, the icon should look flush with the surface
I can't tell either. Probably has to do with the 'theme' we're running. But what I did was customize the toolbar and put it up there. Very easy to see.
Horz. zoom in tight on the timelne. Drag a clip side to side. Snaps at frames spacing with quantize activated. Smooth slide with off.
Alt. arrow will also set your cursor by frames with quantize off. I doing that with version 2 and no quantize.
Things that might cause jitters. Known bug in version 3a that won't resample all clips that have it activated. Fixed in 3b ? 3c ?
Field order switch? Hidden clip under speed adjust clip? Speed is divisibe by source frame rate?