Did you disconnect anc? This is widely recommended in this thread and others. ANC uses RPMs as one of its inputs, so my guess is that it is the engine load, not the fact you just started driving, that is the causative factor.Did you get this figured out? I just put a sub from another car in my 2017 CRV EX, and it's doing the same thing. When I first start driving, the sub goes to full volume intermittently. It never did that in the other car, so I'm pretty sure the line out converter is picking up some noise.
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