Both Rock 105 owner Cox Radio and Clear Channel have been modifying some formatic approaches in Jacksonville. Clear Channel recently re-positioned modern rock “Planet” WPLA (107.3) to classic hits, and that encouraged Cox to adjust WFYV (104.5) from an 80’s-based rocker to active rock, as “Rock 104.5, Jacksonville’s Best Rock.” The Florida Times-Union/Jacksonville.com says “Cox now commands three rock formats – a classic hits 1970s-80s format represented in its ’96.9 The Eagle [WJGL]‘, newer alternative rock in its X102.9 [WXXJ], and now active rock, in Rock 104.5.” WFYV is keeping the AC/DC and Van Halen tracks while adding Rage Against the Machine and current artists like Breaking Benjamin and Shinedown. That evolution follows last week’s drop of the out-of-market Greaseman and the Cowhead show. The station now promises an Arbitron-friendly “52 minutes of music an hour” plus Bubba the Love Sponge in mornings. The Jacksonville market changes from paper diaries to the electronic PPM effective with the December survey. The North Florida Board of Radio-Info has been talking about the strategic rock battle, here.