I bought this civic over the summer and during the winter it is quite loud in the cabin for about 20-30 minutes while being in Park, letting off the accelerator, or in neutral. It doesn't shift hard, doesn't have power issues, it's just really loud, low vibrations. When you shift to drive, it gets normally quiet and acceleration is fine.

After about 20-30 minutes, it's perfectly fine and quite like I expect a Honda to be. A few months ago I checked and drained the transmission fluid from the drain (which is not all the fluid?) and everything was just fine there and it made no change.

I'm kind of at a loss what to look at next.
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