Nyrius NPCS600 Instruction Manual page 12

Bad Audio/ Make sure that the source is outputting supported audio formats.
No Audio
Make sure that the TV's volume is turned UP and not on MUTE.
Make sure that your PC / Laptop audio volume has been turned UP.
Make sure that your PC / Laptop audio output has been switched to
HDMI out.
Make sure there is no 5.8GHz wireless phone within 50cm of the
Receiver. Some phones use substandard transmission schemes.
Other If any other issue occurs or if the above issues persist, try
disconnecting both Transmitter and Receiver and repeating the
pairing process.
For further questions or inquires, please contact NYRIUS customer support at:
www.nyrius.com/contact
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