Blake Shelton and Miranda Lambert have been discounting media reports that their marriage is going downhill. But with their numerous arguments over the past several months, fans are unclear as to whether the relationship will last.

While Shelton, 36 had wanted Lambert, 29, to be his celebrity mentor this season of The Voice, she had turned him down because she was concerned there would be conflicts with her touring schedule, according to a source. But this had caused some arguments between the couple, Radar Online reported.

“Miranda had issues with Blake’s wandering eye with fellow past contestants on the show, but it was his recent Twitter flirtation with Cady Groves that really got her steaming mad,” said the source, based on the report.

The source added, “Miranda has been giving him a taste of his own medicine and showing him that two can play at this game. She’s been flirting with a few of the single guys on her tour, even their good friend Luke Bryan who’s happily married, and it’s conveniently gotten back to Blake.”

While the source said Lambert has more to worry about because of Shelton’s cheating history, he said they are both playing games, and this is adding to the tension.

The Honey Bee singer was still married to his first wife Kaynette Williams when he fell for Lambert in 2006. Shelton and Lambert married on May 14, 2011.

The Voice judge made headlines when he exchanged flirtatious Twitter messages between him and singer Cady Graves, and fueled reports that he was carrying on a month-long affair with the 23-year-old brunette pop-country star.

But Miranda has previously said in interviews, “Divorce is not an option.”