HDMI is commonly used for both multi-channel audio and video/audio in a blu-ray player and Cable set-top TV boxes.
For two channel audio, i2s protocol was adopted. But to this day, there is no standardization with i2s protocol. Some manufacturers are using HDMI and some are using Ethernet ports to convey digital audio between two compatible devices. Unless you buy two compatible devices that uses i2s protocol from same manufacturer, you are very likely to run into ‘hand shake’ issues.
For example, Rockna is using i2s protocol via HDMI ports to convey digital audio between their streamer and DAC. Whereas AQUA is using Ethernet port between their CD player and DAC.
For two channel audio, i2s protocol was adopted. But to this day, there is no standardization with i2s protocol. Some manufacturers are using HDMI and some are using Ethernet ports to convey digital audio between two compatible devices. Unless you buy two compatible devices that uses i2s protocol from same manufacturer, you are very likely to run into ‘hand shake’ issues.
For example, Rockna is using i2s protocol via HDMI ports to convey digital audio between their streamer and DAC. Whereas AQUA is using Ethernet port between their CD player and DAC.