Stocks mostly stumbled after the close Wednesday, and among the most-heavily traded losers was Whole Foods ( WFMI).

The organic-food supermarket chain slid 9.4% to $41.49 after missing first-quarter revenue estimates and hinting it might have regulatory trouble with its planned buyout of Wild Oats ( OATS). Shares of the latter recently lost 1.8% to $17.78 after hours.

Wedding-planning Web site The Knot ( KNOT), based in New York, sank 13.5% to $19.40 after per-share first-quarter income sank by 2 cents from last year to a nickel -- 3 cents short of expectations, according to Thomson Financial.

Infosonics ( IFON) took a nosedive after the San Diego-based wireless-products distributor swung to a first-quarter loss of 3 cents a share (non-GAAP) vs. analysts' projections for 3-cent profits. The small-cap company's shares plunged 20.4% to $3.12.

Among other postbell losers, Texas-based semiconductor Cirrus Logic ( CRUS) foresees lower-than-expected revenue of $40 million to $44 million in the quarter ended June 30, and apparel retailer American Eagle Outfitters ( AEO) reported a year-over-year drop in both revenue and same-store sales for the month ended May 5. Cirrus shares lost 8.5% to $7.90 as Pennsylvania-based AEO shed 1.8% at $28.45.

On the flip side, however, San Diego's WebSideStory ( WSSI) soared more than 19% after hours on word that the business-services firm ramped up first-quarter non-GAAP income to $3.3 million, or 16 cents a share, from last year's 12 cents a share. That tops analysts' estimates by 2 cents a share, and revenue also came in higher than expected. Shares added $2.13 to $13.25.

Dallas-based Home Solutions of America ( HSOA), another business-services firm, jumped 11.4% to $5.85 after its first-quarter profit totaled 12 cents a share, 2 cents better than the sole analyst's estimate. Semiconductor-equipment maker Brooks Automation ( BRKS), of Chelmsford, Mass., also beat by 2 cents. Shares climbed 1.5% to $18 in recent late trading.