- Different settings of HDMI Audio
- Different settings of Bitstream
- Different settings of HDMI Startup Mode
- Check whether analog audio (white and red RCA connectors) has output
One more thing. HKTV outputs 44.1kHz audio instead of 48kHz like TVB/ATV/RTHK or common broadcasts in the rest of the world. Please check your TV supports HDMI audio of 44.1kHz. You can verify that by playing a CD in a HDMI DVD/Blu-ray player.