Adduct in GC-MS?

[Fabiano]

have anyone ever heard that GC-MS with electron impact could generate adducts? more exacly proton adducts.

I´m performing a TMS derivative analysis and some of my peaks are giving 1 mass unit higher than literature, even standards.

other people insist that the equipment is calibrated.

thank you

[wra]

You need to tune your GC-MS.

[Fabiano]

but if peaks of other give me right spectra and only mine is 1 unit higher, is there some explanation?