British singer-songwriter Imogen Heap is finding it increasingly difficult to tour due to the cost, and lagging album and ticket sales, according to the Guardian. The artist, perhaps best known for the hit “Hide and Seek,” recently lamented on her Twitter page that due to a “monopoloy” in the U.S. market for concert venues, fans are forced to pay a “huge mark up” on the price of tickets. Heap’s album sales also help pay for her tours, and vice-versa, according to the Guardian, and those have been slow. “With few album sales there’s little to pay for the tour. I can’t sustain it. Time to rethink!” she wrote.