Boyd Tinsley has been accused of "creepy, sex-based behavior" and "sexually predatory harassment" from April 2015 - August 2016

Boyd Tinsley, the former violinist for the Dave Matthews Band, has been accused of sexually harassing an ex-bandmate.

Former Crystal Garden trumpet player James Frost-Winn filed a lawsuit in Washington on Thursday, claiming Tinsley, now 54, was “sexually flirting with verbal sexual comments, physically touching [and] sexting” as well as alleged “creepy, sex-based behavior” and “sexually predatory harassment” from April 2015 through August 2016.

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Frost-Winn is suing for damages for “loss of enjoyment of life, pain and suffering, mental anguish, emotional distress, and humiliation.”

In court documents, Frost-Winn provided various incidents as well as screenshots of text messages between the pair, with one of the exchanges from Tinsley stating: “You’re such boner material and I want you at your best. I’m actually masturbating to the thought of your shots.”

Image zoom Dave Matthews and Boyd Tinsley Sylvain Gaboury/FilmMagic

On Feb. 2, Frost-Winn’s lawyers reportedly sent a demand letter to Tinsley, looking for an out-of-court settlement for assault and harassment, according to Consequence of Sound.

That same day, Tinsley, who has two children with wife Emily, announced on Twitter that he was taking “a break” from touring and from the Dave Matthews Band to “focus on my family & my health.”

A rep for the Dave Matthews Band tells PEOPLE: “Though Boyd is no longer a member of the band, we are shocked by these disturbing allegations and we were not previously aware of them.”

A rep for Crystal Garden did not immediately respond to PEOPLE’s request for comment.

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The same day the lawsuit was filed, Frost-Winn spoke with Consequence of Sound, claiming that he is seeking $9 million in damages.

He met Tinsley in fall 2007 when he was 18 years old and homeless. They had struck up a friendship for years before he joined in Tinsley’s band, Crystal Garden, in July 2015.

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Frost-Winn recalled one specific incident during a recording session when he fell asleep on the couch in the studio.

“I don’t know how long I was asleep, but when I came to, he was masturbating next to me while I was sleeping, and he had his hand on my ass,” he said. “He was climaxing. I felt assaulted. It was something I didn’t expect from him. I was contemplating how to stay in the project — it’s such a big opportunity, but my trust had been affected.”

Image zoom Dave Matthews and Boyd Tinsley in January 2010

On Monday, Dave Matthews spoke about Tinsley’s exit from the band, revealing to Vulture that there are no immediate plans for his return.

“I can’t say, ‘I can’t wait till he comes back,’ because I don’t know what’s going to happen. But right now being away is better for him. Nobody is happy about this situation. Except that we’re happy he can figure some stuff out,” Matthews, 51, said.

“I hope he does. But I’m going to miss having that whirling-dervish Adonis-Muppet over there on my right. I know the audience is, too. But we can’t serve that desire,” the frontman added.