The optical audio port, also known as TOSLINK, can be useful for connecting older sound systems or linking devices like soundbars to TVs. TOSLINK cables use fiber optic technology to transmit digital audio signals, which makes them distinct from other types of audio cables that use electrical signals.

If you think you have an optical cable or audio optical cable that has gone bad, there are a few different tests you can run to check the cable. If you notice crackling noises, distorted sound, or loss of sound, this is a good indication that your audio optical cable is going bad.

The wider the skirt, the higher the jitter. This means the external sound card introduced more jitter to the sound. Therefore not all optical outputs are created equal. Side note: The spikes on either side of the 1000 kHz tone are intermodulation distortions caused by the 60 Hz noise in power supply.

The recommended length for optical cables is 10 meters, although some people still use them with a length of 30 meters. For longer distances, optical cables are a good choice. For HDMI, there are no such recommendations. But we recommend HDMI when the distance is 5 meters or less for the best quality sound.