T4c is a big one: part stabilization, part new features, on top of T4b, and the most contributor-driven build yet. swmarks rebuilt the CEC and screensaver handling, samtheruby backported the newer CEC kernel driver, fixed SD/VESA display modes and built in-GUI update channels, Sebastiii contributed MKV editions support, an Epson projector profile and DV fixes, and vlix wired the skin's codec logos into the DV pipeline and brought DV profile info to the library. On top of that: VC-1 hardware playback overhauled, a self-healing A/V sync layer for corrupt streams, AC-4 audio decoding, a nasty resume bug, per-frame tone mapping for DV→SDR, and a stack of DV picture fixes.
The headline changes:
- CEC behaves now. The box no longer powers itself on when the TV or AVR switches inputs, no longer steals the TV's input back after you switch away, reliably puts the TV into standby on power-off, and a stuck CEC bus can no longer freeze the UI