As a general rule, I don’t think midwesterners have very pronounced accents, particularly in the Kanasa-Nebraska-Iowa-Ohio parts, and the way of speaking is really close to dictionary English.
The only deviation I know of is that people tend to pronounce “wash” as “warsh” — and I’ve even seen a few people spell it that way when I was in school.
And, in a weird recent one, there was a tv commercial where they were wanting crayons donated to children and promounced them “crowns.” And it took me a while to figure out what they meant… crowns like kings wear? Dental crowns?
And,speaking of southern accents, a couple of years ago I called up DirecTV customer support, and the woman I spoke to had a really thick southern accent. She kept telling me to hold down the MUTE and SELECT buttons at the same time, but she pronounced “mute” like “me-you” and I thought she meant the MENU button… Took me forever to figure out what she meant.