Terrestrial radio advertising dollars remained flat last quarter, raising questions about the overall health of the format. According to figures recently released by the Radio Advertising Bureau (RAB), both local and national revenues stayed level for the latest three month period. That mirrors the performance from the first quarter, with overall 2005 revenues inching up just 1 percent over the first half of 2004. That data continues to ring alarm bells, with big threats continuing to come from portable MP3 players and premium satellite radio offerings. ¶ The latest developments also come against major advertising increases in the online space. ... Link: Digital Music News.