Pandora (P -4.6%) slides after releasing April audience metrics that suggest its 40-hour mobile monthly listening cap is taking a toll. Listener hour growth of 24% Y/Y (to 1.31B) represents a sharp slowdown from March's 40%, and Pandora's share of U.S. radio listening fell to 7.33% from March's 8.05% (it's up from the year-ago period's 5.95%). Active listeners totaled 70.1M, up 35% Y/Y but only 1% M/M - that last figure suggests slowing U.S. smartphone market growth and/or competition from the likes of Spotify, TuneIn, and Songza might also be having an effect. FQ1 results arrive on May 23; shares are still up 53% YTD following a well-received FQ4 report.