NXP Semiconductors NV (NASDAQ: NXPI) saw its shares plummet 5.38% in after-hours trading on Monday, despite reporting second-quarter earnings that beat analyst expectations. The semiconductor manufacturer's mixed third-quarter guidance and year-over-year revenue decline appear to have spooked investors.

For the second quarter, NXP reported adjusted earnings per share of $2.72, surpassing the analyst consensus estimate of $2.67. However, revenue came in at $2.93 billion, marking a 6.43% decrease from the same period last year, although it still marginally beat the expected $2.90 billion. The company's adjusted gross margin stood at 56.5%, while the adjusted EBIT margin was 32%.

Investors seem particularly concerned about NXP's outlook for the third quarter. The company projects revenue between $3.05 billion and $3.25 billion, compared to analyst estimates of $3.05 billion. The wide range and the lower end matching analyst expectations may have contributed to the stock's after-hours decline. Additionally, NXP's Q3 adjusted EPS guidance of $2.89 to $3.30 encompasses the analyst estimate of $3.06, but the broad range adds to uncertainty. Despite these concerns, NXP's CEO, Kurt Sievers, noted "an emerging cyclical improvement in NXP's core end markets," which could potentially signal better performance in the future.