Chirrup chirrup… is it a nightjar?

For a month or so, since I’ve had my window open in the evening while I’m working, I’ve heard a bird nearby with a strange call. He – or she, spends most of the evening making a rasping chirruping churruping noise, and even if I’ve worked into the hours of the early morning, I can still hear chirrup churrup. It’s difficult to transcribe but pddddddddup pddddddddddddup would be nearest to it…

I thought it might be a seagull because they make strange noises, but I didn’t think a single gull would roost near here or roost on its own. I wondered if it was a night jar but they seem to make a longer call lasting tens of seconds in the recordings I’ve heard and this bird makes to noises and then is silent for a while . I also wondered if it might be a very loud toad, but it really sounds bird-like…

I need an expert to come and listen to it!

A nightjar, by the way sounds like this: