"He thinks their next album is the perfect time to create a much edgier and more rock 'n' roll image and he's already writing songs that he wants them to include on the record," the source said.The band members fear that if the demands of the singer are not fulfilled, he might plan to go solo.
"The problem is the rest of the band fear if Harry starts changing their style he's going to take over the whole thing. Niall and Louis especially are worried about turning their backs on a pop sound and changing a winning formula," a source said.
"The fear is that if Harry doesn't get his way he could end up walking out and going solo. He doesn't want to be five years down the line and still doing boyish pop tunes," the source added.