Apple trouble? Another iPhone supplier disappoints

A customer checks an iPhone 6s at an Apple store.
Chesnot | Getty Images

Another day, another disappointing report from a supplier to the iPhone.

Knowles, a microphone maker, fell more than 15 percent Tuesday after saying the prior evening that sales this quarter may fall short of Wall Street forecasts.

UK-based Dialog Semiconductor, a maker of power management chips for the iPhone, lost a fifth of its value in European trading Monday after saying something similar in an earnings pre-announcement. Dialog gets 75 percent of its sales from the iPhone, according to estimates.

Other suppliers like Skyworks Solutions, Avago, and Cirrus Logic are down 4 percent or more so far this week.

If the companies that supply parts to the iPhone are disappointing investors, does that mean Apple will as well when it reports quarterly results after the close Tuesday?

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