This word in the end (th) sounds like an "d", as "wid"

Anytime! And I hope you find your British person...it seems like a lot of people are leaving this site to the new design.

Thanks laralogic. I thought that there is a rule so I asked this question. I wish to find an answer from a native British.

I really wish I could answer this question, but it's not easy. I had to say a bunch of sentences out loud to myself and try to think. I can't speak for Brits, but for Americans sometimes it's laziness in speech (both intentional and unintentional) when we use wɪð. Other times it obviously depends on the words in the sentence, but it's not always due to a particular letter. I don't think there's a pattern to it.