The novel solution provides a method for feeding of individual envelopes from a stack of envelopes in a hopper for an inserter machine. At the downstream end of the hopper, a friction feeder serially feeds individual envelopes from the stack. A suction cup is selectively actuated to engage with the envelope to pull a leading portion of the envelope away from the stack to assist the friction feeder in feeding envelopes. Selective actuation is based on monitoring downstream movement of fed envelopes. The suction cup is engaged when the envelopes travel a shorter distance than would be expected based on the movement of the feeder.