If this product doesn't have an external power supply, it's in violation of the HDMI spec, which says you can't use the HDMI cable's 5 Volt rail to power downstream devices.
The spec is there for a reason - if you pull the voltage down more than 0.3 volts, the HDCP handshake can fail.
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If this product doesn't have an external power supply, it's in violation of the HDMI spec, which says you can't use the HDMI cable's 5 Volt rail to power downstream devices.
The spec is there for a reason - if you pull the voltage down more than 0.3 volts, the HDCP handshake can fail.