A:Answer Using the coffe ground basket (light brown), looking inside (before you fill with grounds), there is an indentation/max fill line inside... it maybe that your putting to much grounds in, causing the basket to clog up, water displacing elsewhere.
Additionally, I find its always best to use the same size cup to fill the resivor to insure yyour not exceeding the cups size.
One other thing... If your brewing a small cup, use the riser that came with the maker to insure the brew goes directly in the cup, and, make sure your cup is placed against the splashguard.
Note: The small tray that catches minimal overflow irs best to empty/clean regularly.