Who was the hottest music ticket at this year’s CES gadget show in Vegas?

Lady Gaga surprised revelers at an Intel party, and Beck and Elton John likewise showed up for geeky gigs.

But according to our source, the sleeper chanteuse may have been Randi Zuckerberg, who took the mic at a late-night karaoke party she co-hosted at a penthouse in the Venetian with mobile app AmpMe on Jan. 6.

“She sang ‘Son of a Preacher Man’ and she was f–kin’ awesome,” one attendee gushed. “She’s got some pipes on her.” The Facebook founder’s 33-year-old older sis, who starred in the “Rock of Ages” Broadway show in 2014, also sang Adele’s “Hello,” partygoers said.