I've hooked up a knock sensor with a small audio amplifier and some headphones. Was driving around familiarizing myself with the noise of the engine so I'll be able to identify when knock occurs.

it's fascinating the detailed sounds I can hear. It sounds like I can hear every combustion event, like a squishy sound.

But at cruise speed and kind of a neutral load, just maintaining speed, there's a kind of chatter . I,m wondering if that's from the apex seals? It goes away if I lift, or if I increase load at all. Just happens at that cruise/low load condition

Has anybody else experienced this?