Help! Mouldy seed plugs

[BlowDryRat]

I bought a couple of plugs trays (link) to get my seeds started. The seeds are germinating but the plugs have gone mouldy and smell awful. I've drained them and left the lids off to try to dry them out a bit. Is there anything else I should do?

They need horizontal airflow.
Are they inside or in a cold frame?

They're inside on a windowsill.

I've opened the windows to either side to get some airflow. Fingers crossed!