Customers on AT&T's wireless network in Ann Arbor and other southeast Michigan communities may have noticed that connections weren't exactly working smoothly.

That service glitch ended at about 4 p.m. Friday, according to AT&T officials.

"AT&T located a connection issue with one of our VOIP service packets," said spokesman Jermaine Spight in an email to AnnArbor.com.

That connection issue was noticeable on Thursday and early Friday, customers said. Some complained of dropped calls, while others said they had a difficulty making connections. Another problem was distorted sound once a call was connected.

Spight said he didn't have information on when the service problem started, but it affected customers in Dearborn Heights, Canton and New Hudson, in addition to Ann Arbor.

By 4 p.m., however, the issue was resolved, he said.

Spight also said he didn't have an estimate for the number of customers affected.

AT&T is the world's largest communications holding company, according to corporate data, with $124 billion in consolidated income in 2010.

It serves about 95.5 million wireless customers in the U.S.