Interviewing Tinashe in 2017 is to witness patience and resolve in action. Despite releasing a handful of pop-R&B bangers (the DJ Mustard co-produced 2 On; certified bop Player; current single Flame); a coterie of elegant, so-called alt-R&B jams (all of 2015’s Amethyst mixtape); and being hailed by the likes of NME and Pitchfork as the next Aaliyah, her career has unquestionably stalled.

Joyride, the follow-up to 2014’s critically lauded debut Aquarius, has sat unreleased by her label since it was announced 18 months ago. Singles have come and gone; various collaborations (Tinie Tempah, KDA, erm, Enrique Iglesias) have barely charted; and here we are, in the belly of the beast, AKA her label RCA’s west London offices, quietly fuming. Or at least I am. Tinashe, slowly working her way through an English breakfast tea, has no time for negativity.

“Things haven’t always gone according to my original plan,” she says calmly, “but that’s life, and things change.” Any normal person in this situation might want to flip a table in frustration, I suggest. “However long it takes, I know I will get to my end goal,” she says. “I’m never going to stop. I will make music forever.” To prove her point, the background image on her phone is a generic picture of a Grammy, and it will stay like that until she can swap it for one of her own. “It’s been like that for years!” she screams in mock horror.

Watch the video for Flame.

Such unshakeable determination has defined 24-year-old Tinashe Kachingwe’s life so far. A budding actor and dancer from the age of five, her parents – Zimbabwean-immigrant father Michael and Danish mother Aimie (TinasheMomma on Instagram) – uprooted from Kentucky to Los Angeles to keep up with her auditions. “I was very aware of my parents and our financial situation,” she says of the pressure. “We always figured it out, but I knew we couldn’t afford to live in Los Angeles. My parents are from Iowa, and we were barely getting by in LA.”

As the acting roles piled up, including a recurring role on sitcom Two and a Half Men, Tinashe quit school. “There was a lot of misplaced jealousy, so I didn’t want to be there any more,” she shrugs. In 2007, she joined the Stunners, a girl group briefly signed to Columbia whose greatest achievement was opening for Justin Bieber on 20 dates of his first world tour.

Being in a band streamlined Tinashe’s focus towards music. It also gave her an early insight into the world of production: “I learned how to record in big studios and how to engineer and create songs.” After they split in 2011, she taught herself Pro Tools from YouTube tutorials, creating her first mixtape, 2012’s In Case We Die, in her home studio. That helped her to land a deal with RCA, which, for Tinashe, coincided with the realisation that her thirst for knowledge wasn’t always going to be seen as a positive. “There’s a lot of sexism in the music business,” she says, calmly flattening the creases in her floor-length silk coat. “A lot of sexism. As far as female producers or female engineers … when you’re in these studios, it’s all men. It is so rare that they’d not even expect me to have an opinion.”

That studio-based sexism is something she feels also permeates the music industry more generally, and has been a factor in her stop-start career so far. “It’s so much easier for male artists, I know it is,” she says. In early 2016, months after Joyride’s announcement, a Twitter message, apparently from Tinashe, emerged claiming that part of the hold-up was down to her label focusing on “Zany”, AKA the newly solo Zayn Malik. “I sent that message, yeah, that RCA was focused on Zayn? They were! But I have nothing against him; more power to him.”

Despite high-profile nods of respect via tour support slots with Katy Perry and Nicki Minaj, collaborations with Britney Spears (“An icon”), and being hand-picked by Janet Jackson to perform at her 2015 BET awards tribute (“I died … Dead”), she feels that her male counterparts have been less supportive. “Male artists don’t really co-sign female artists like that, and if they do it’s always like, ‘Are they fucking?’ It’s never, ‘Oh, I really like her music.’”

She is also calling bullshit on the idea, perpetuated recently by warring Twitter fan-tribes, that there’s only room for a couple of successful black female artists at any given time. “Recently, my cousin was with a friend of a friend, who was in high school, and she was like: ‘I’m a fan of Kehlani,’ but in a way that was like, ‘So I can’t be a fan of Tinashe, too.’ Then my friend posed the question, ‘Why not be a fan of both?’ It’s kind of like sport; people feel like they have to pick a side.” Suddenly she springs forward, her default laid-back demeanour temporarily out of the window. “There are hundreds of [male] rappers that all look the same, that sound the same, but if you’re a black woman, you’re either Beyoncé or Rihanna. It’s very, very strange.”

Backing singers ... Tinashe performs with Britney Spears in December 2016. Photograph: Kevin Winter/Getty Images/iHeartMedia

Ciara – another all-round performer with a handful of stone-cold bangers – has suffered similarly through comparison, I suggest. “I’d agree,” she nods. “It felt like they almost had to sacrifice someone because there wasn’t enough room, which isn’t true. Ciara’s an amazing artist, Beyoncé’s an amazing artist, Rihanna’s an amazing artist, and they’re all very different!”

Tinashe’s mixed-race heritage, which was used “as another example of why I was different” during those difficult school years, also remains an issue. “There’s colourism involved in the black community, which is very apparent,” she says carefully. “It’s about trying to find a balance where I’m a mixed woman, and sometimes I feel like I don’t fully fit into the black community; they don’t fully accept me, even though I see myself as a black woman. That disconnect is confusing sometimes.” A shrug. “I am what I am.”

She confirms the rumour that Rihanna, or someone from her team, heard Joyride’s title track and briefly swiped it for her own album. “Yeah, that’s true,” she says with typical breeziness. “But I don’t know if it was personally Rihanna, like, ‘I’m taking that from Tinashe.’ I don’t think that’s how it worked. But it’s back now.” Despite all these setbacks, all these things she can’t control, she’s adamant that she’s never once thought of quitting. “It’s definitely been discouraging, and I have days where I’m less confident, but at the end I know that I’m going to get to where I need to go.” She shuffles in her seat. “There’s doubt that seeps in, there’s self-deprecation, because you look to someone to blame and you can’t blame anyone but yourself, but I’ve never, ever thought, ‘I’m going to work in a mall.’”

Pop life ... Tinashe (far left) as one-fifth of the Stunners. Photograph: Raymond Boyd/Getty

Late last year, she had a minor breakthrough when RCA released Joyride’s hastily announced companion album Nightride, an after-hours, minimal-sounding stop-gap collection featuring the likes of Dev Hynes and the-Dream. Considering Joyride’s tortured gestation, Nightride’s release felt oddly hassle-free. “I think by setting the scene differently for the label – like, this is not ‘the album’ – it made it, like, ‘OK, it’s just a project,’” she says. Did it feel like the label was appeasing her? “There was a little bit of that, yeah, but at the same time they’re aware that my fanbase wants new music.”

Perhaps at the core of Tinashe’s delayed ascendancy is her lack of an undeniable, bona fide smash hit; one that would fully capture RCA’s attention and shuffle her up the pecking order (at No 24 in the US, 2014’s 2 On is her highest-charting single to date). She could, in theory, keep chucking out low-key mixtapes and luxuriate in critical acclaim, but – having grown up on pop stars such as Michael, Britney and Christina – she’s aiming for superstar status. “I consider myself a pop artist who makes R&B-tinged pop music,” she says adamantly.

As for Joyride, well, it’s coming. Soon(ish). “It’s not like it’s sitting in a vault locked up, it’s always getting better and improving,” she says. “I plan on doing a solid few more months recording then hopefully getting it out this year.” She notices my involuntary eye roll at that word “hopefully”. “It’s going to be great,” she states. “They’re going to be the best songs!”

Flame is out now; Tinashe plays Koko, London NW1, on Thursday 29 June