T-Mobile is going to fork over $40 million as part of a settlement with the FCC.

The Federal Communications Commission announced today that it's reached a settlement with T-Mobile regarding failed calls to rural consumers. The FCC received complaints that T-Mo customers were unable to reach customers of three rural Wisconsin carriers. And though T-Mo told the FCC that it had fixed the problem, the FCC continued to get complaints about failed calls.

What's more, T-Mobile has admitted to injecting false ring tones into hundreds of millions of calls that didn't connect. That's a violation of an FCC rule that prohibits injecting false ring tones into any calls.

T-Mobile has been found in violation of the Communications Act of 1934 and will pay $40 million to the U.S. Treasury as part of its settlement with the FCC. It will also enter into a compliance plan to prevent future violations from happening.