The Sieg X2 is a small mill with a 1/3 HP spindle motor so it's not intended to be too aggressive in the works requested of it. Some ideas of what you are cutting, how and the speeds and feeds along with the tooling being used would be useful.
First things might be to check if the machine holds position when doing air cuts over long periods, then perhaps to use lighter loads (lower travel speeds and lighter cuts).
Cheers,
HarryE.
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