2003 subaru outback, breaks click sound when in park

I have a subaru outback, 60k, automatic. When it’s in park, I hear a clicking sound when I depress the break pedal and also when I release it ? any thoughts as to what this is?

It just started a few days ago.

What you are hearing is the brake/transmission interlock. This prevents you from shifting out of Park unless the brake is depressed, and this system normally makes a slick clicking sound when the brake is depressed.

Why you never heard this noise previously is something that I cannot explain, but it is entirely normal.

Thanks for the info - I just purchased the car a few weeks ago which is why I probably never noticed it. I assumed it was a new development but given the limited length of ownership and your explanation it was likely there all along and I never noticed.