The answer to 'why is my shut-off valve making gurgling noise' is that the gurgling sound is likely caused by a problem with the shut-off valve itself. This could be due to a buildup of debris, a worn-out valve, or a problem with the plumbing system.
Gurgling sounds from a shut-off valve often indicate that there is an issue with the valve's ability to properly open and close, which can lead to water pressure fluctuations and the gurgling noise. This is a common problem that can occur over time as the valve components wear down or become obstructed.