I've definitely noticed that when adding layer 3 interfaces to a stack the other switches have to sync the config. But I haven't noticed the interruption. Is the L3 stuff you are working on in the same subnets as your phone/voice VLANs or completely separate?
Adam R MS | CISSP, CISM, VCP, MCITP, CCNP, ITILv3, CMNO
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