The tools are generally heavier on the bottom than the top. If the clamping fingers spring has gotten filled with chips or the fingers are not pivoting freely then the tool may be held but just not tight enough. When the carousel turns it would throw the bottom out and tilt the top of the tool inward.
When I bought my current VF-2, I had to drop the carousel, disassemble, clean everything and reassemble it. Works perfect now. Constant coolant splash and chips tend to gum up the works. Remember that when the coolant enters, only the water in it leaves. The water evaporates leaving the oil behind. The oil gets hard over time and makes things stick.
Check it out for that.
Cheers---Mike
Two Haas VF-2's, Haas HA5C, Haas HRT-9, Hardinge CHNC 1, Bother HS-300 Wire EDM, BobCAD V23, BobCAD V28