I am using it for I2S.
What should be the result?
I2S was designed to allow two chips on a board to communicate 2-channel digital PCM samples, without any error detection or correction. The secret of digital when done properly is that errors can be both detected and corrected. The original digital can be restored even if the transmission is faulty.
I2S uses four connections but was never designed in 1986 to operate over a cable. To quote Wikipedia
The I²S connection was not intended to be used via cables, and most integrated circuits will not have the correct impedance for coaxial cables. As the impedance adaptation error associated with the different line lengths can cause differences in propagation delay between the clock line and data line, this can result in synchronization problems between the SCK, WS and data signals, mainly at high sampling frequencies and bitrates. As the I²S bus doesn't have any error detection mechanism, this can cause significant decoding errors.
Most HDMI connectors have 19-pins so can easily provide the 4 pins needed by I2S. It is an absolute bastardisation of the brilliant HDMI standards to steal its cable and connectors for I2S!
Currently HDMI is designed to transmit 48-Gbps rising shortly to 96-Gbps. That's phenomenal. But you can't extend the cable too much beyond a few metres. Transmission will start to break down with obvious effects, particularly for video.
With I2S any length is problematic. As I said, all bets are off