Have you had other guests stay before? Any issues? I would not offer credit after checkout unless there was something unexpected. Not great guest behaviour. This is part of how your listing is, and I assume not something you can turn off. When guests check in, I usually tell them to call me if there is anything at all, day or night, that I can help with or that they can't work out. I want to know about problems when they are in residence, not afterwards!
If your place is truly noisy, I would say so in the listing (in a nice way) and price accordingly. For instance ''some night time noise from outdoor fan in second bedroom, hence the lower price on that room''.