Fast food is getting slower ... again.

The average drive-thru time has jumped to just shy of 222 seconds, according to QSR Magazine's annual study of drive-thru orders. This represents a slowdown from 203.29 seconds a year ago.

The slowdown is "pretty significant" the QSR said, as chains continue to grapple with the impact of menus that offer more ways for customers to craft their own meals, said Sam Oches, the magazine's editor

"I think the trend has continued. What we started to see a couple years ago is increased times. Customization and enhanced menu items are slowing things down," Oches said.

This year's study included results from 29 chains and data from 1,882 different visits at 890 different restaurants. The time is also much slower than results in 2011 to 2013, although fewer chains were included in those earlier years.

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There is a silver lining for fast-food diners. Order accuracy is improving at chains — great news for anyone who has had to make a U-turn on the highway to retrieve missing fries.

Orders are now accurate 88.8 percent of the time, up from 87.2 percent last year, QSR found.

So what's a fast-food diner in a hurry to do?

"Here's a general rule of thumb: The later in the day, the longer it's going to take," Oches said.

"What the restaurants are telling us is they're staffing their best people for breakfast and lunch," he added.

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