San Bruno-based company YouTube has always had a testy relationship with music publishers and media conglomerates, as indicated by a spate of lawsuits filed in the last few years — starting with Viacom, which charged Google with copyright infringement back in 2007. Last year, a district court in New York absolved YouTube of responsibility. Viacom is in the process of appealing that ruling and seeking $1 billion in damages. Meanwhile, the National Music Publishers Association took another strike at YouTube, alleging that the company broadcasts music videos without authorization. Google helped broker a deal between the two parties, stipulating that the NMPA license its content to YouTube, in exchange for royalties. Apparently, the settlement left everybody happy. This morning Bloomberg News reported that NMPA had dropped its appeal of a lower-court ruling in favor of the defendant.