From page 20 of the Pio51 manual:
Caution
• When HDMI is selected for Video, no video signals are output
from the COMPONENT VIDEO, S-VIDEO or VIDEO output
terminals.
• When Component Video or S-Video/Video is selected for
Video, no video signals are output from the HDMI OUT
terminal.
• The video and audio signals output from the set output terminals
are output synchronously (lip synchronization).
• When S-Video/Video or Component Video is selected at
Video, no sound is output if HDMI is selected at Audio (the
warning message shown below is displayed).
Follow the procedure below to redo the connections, then select
the proper connection at the setup screen.
Jason