San Diego-based Slacker, which operates an Internet radio service, along with selling a music player linked to it service, has reportedly scored a $5M bridge financing round, according to industry publication VentureWire. VentureWire cited a regulatory filing in reporting the news. Slacker is venture backed by Austin Ventures, Centennial Ventures, Mission Ventures, and Sevin Rosen Funds, and had previously raised $53.5M in funding.