VHF volume getting quieter

[Bycrick]

I’ll try to beat my autofill into submission. Another story of the same reported problem. About 1978, a $1000 Motorola VHF radio. One of the first to not use crystals for different channels. Mounted face up in an open boat cockpit. No audio. Opened it up. Everything looks perfect. Voltmeter shows audio at the speaker terminals. Coil resistance is fine. Clip on a test speaker and it works. After taking out the old speaker, I found that Motorola had used a waterproof speaker that had a very-thin membrane over the front. An invisible pinhole had allowed water to slowly collect until the entire speaker cone was full.