Couple other things to check...
Remove the dials from your crossfeed and compound -don't lose the little tensioning tab between the dial and the slip collar. Make sure the plate (behind the radial thrust bearings) that holds the ACME screws are tight. The acme screw for the x-feed has a split tab it threads into... adjust the set screw in the split tab to remove the backlash. You can remove the little tab by unscrewing the ACME screw then, unscrew the cap screw that's in front of the tool post. The tab will drop right out. Also make sure the screw that holds the tab through the top of the x-feed is tight when you put it back in (this can cause all kinds of weird problems if it's loose).
If that doesn't get rid of the chatter, I'd take the whole compound off, inspect and clean everything. It's not hard to take the compound off. Remove the x-feed plate first to reduce weight (BE CAREFUL... Wear heavy gloves. The dovetail edges are sharp).
I still think there are 2 issues. One is the compound or cross slide. Something is caught in the ways and it's not sitting flat or, there's excess clearance somewhere. Taking a test cut with the carriage lock partially engaged will help rule-out things.
The bearings just went bad for some reason. The dull finish on the race and visible lines in the rollers should not look like that.
Just out of curiosity, have you cut any other type of material? That piece in the picture looks like SS and if you're using raw carbide instead of TiN or TiALN you can get an ugly finish like that and it even gives a little chatter too. That could be what's setting up the vibration and other factors with the compound, carriage of crossfeed are resonating.
Ray