2000 Subaru Outback transmission noise when clutch pedal isn’t depressed

The patient: My 2000 Outback with 220,000KM on the clock

This is my winter beater, it’s been parked for 6 months. Clutch/flywheel/release bearing was replaced 4 years and (20,000km ago). I replaced the transmission mount last week, bolted everything up, and the transmission makes a weird grinding noise when the clutch isn’t depressed. If I’m in gear and driving around, the noise is still there.

If anyone has some suggestions, i’m all ears!

Thanks,

Matt