Internet radio pioneer Pandora took a beating on Friday, as its stock plunged around 25% after a dismal Q4 revenue forecast. And there’s a sign that more trouble is on the horizon: teens are fleeing the service at a staggering rate, according to a recent survey by Piper Jaffray.

Pandora has gone through a flurry of changes over the last year, both in management and strategy, culminating with a CEO change in which cofounder Tim Westergren stepped down in June, and was replaced by former Sling CEO Roger Lynch in August.

In Lynch’s prepared remarks for Pandora’s earnings call Thursday, he acknowledged that he had a tough road ahead of him — “tangible challenges,” as he put it.

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