[Zeke]

Originally Posted by sammyg2

the only reason i can think of that would cause that is if the line from the vent to the sink drain is clogged or partially clogged.
Do you use those soap tablets? Sometimes they don't dissolve all the way and can clog the drain.
Get under the sink, pull the drain line off from the vent to the drain and check that line. It's probably a really easy fix.

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