SigmaTel Portable Digital Audio Technology Drives GPX SportX Headphone MP3 Player

AUSTIN, Texas--(BUSINESS WIRE) -- April 11, 2005 -- SigmaTel, Inc. (NASDAQ:SGTL) announces that its MP3 audio system-on-chip technology powers the latest GPX SportX(TM) digital audio headphone player with digital FM radio.

SigmaTel, as the worldwide market leader for portable digital audio technologies, enables companies such as GPX, to bring to market unique form factor designs such as the SportX player. Through patented semiconductor and software solutions, SigmaTel's integration and support allows customers to develop devices with the longest battery life, smallest form factors and lowest system design costs in the market.

"GPX is working with SigmaTel not only because of their market leadership but because of what their solutions allow us to incorporate into our designs," said Bill Fetter, CEO of GPX. "The GPX brand represents product quality, reliability and value pricing and SigmaTel's solutions allow us to maintain our focus on these important goals."

This SportX design is a one-piece back-strap headphone digital audio player developed for active lifestyles and athletic uses. With a light weight, intuitive design and no cords the SportX is a simple to use design with an affordable price. The HW6805DT will be available in May at select retail and online stores with suggested retail prices as low as $99.

"The SportX from GPX magnifies the extreme applications that SigmaTel-based technology can enable," said Ron Edgerton, president and CEO of SigmaTel. "With a solid design sense and strong distribution channels, GPX has the business model that can succeed in this fast growing market."

Other important features of the SportX include 128 megabytes of built in memory, with future models offering 256 and 512 megabytes. The SportX also features a memory expansion slot for a SanDisk(R) TransFlash(TM) memory module card, the first such application apart from the cell phone market. This expansion card feature enables additional storage capacities between 32 and 256 megabytes on a thumbnail-size card. The SportX features a digital FM radio tuner and supports MP3 and WMA music formats as well as PDDRM (Windows Media Portable Device Digital Rights Management) for compliance with rights protected music distribution services.

For additional information on SigmaTel, please visit http://www.sigmatel.com. For additional information on GPX, please http://www.gpx.com.

About SigmaTel:

SigmaTel, Inc. a fabless semiconductor company headquartered in Austin, Texas, designs, develops, and markets proprietary, analog intensive, mixed-signal ICs for a variety of products in the consumer electronics and computing markets, including portable compressed audio players, such as MP3 players, notebook and desktop PCs, DVD players, digital televisions, and set-top boxes. SigmaTel provides complete, system-level solutions that include highly-integrated ICs, customizable firmware and software, software development tools, reference designs, and applications support. The Company's focus is on providing system-level solutions that enable customers to rapidly introduce and offer electronic products that are small, light-weight, power-efficient, reliable, and cost-effective. SigmaTel is ISO 9001:2000 certified and is committed to providing customers with high performance, quality products along with superior customer service.

Cautionary Language:

This press release contains forward-looking statements based on current SigmaTel expectations. The words "expect," "will," "should," "would," "anticipate," "project," "outlook," "believe," "intend," and similar phrases as they relate to SigmaTel or future events are intended to identify such forward-looking statements. These forward-looking statements reflect the current views and assumptions of SigmaTel, but are subject to various risks and uncertainties that could cause actual results to differ materially from expectations. A number of important factors could cause actual results to differ materially from those in the forward-looking statements, and there will be events in the future that SigmaTel is not able to accurately predict or control. For a discussion of factors that could impact SigmaTel's financial results and cause actual results to differ materially from those in the forward-looking statements, please refer to recent SigmaTel filings with the SEC, particularly the 424(b)(4) final prospectuses filed September 19, 2003 and February 19, 2004, the Form 10-Qs that were filed on October 29, 2003, April 20, 2004, July 20, 2004 and October 19, 2004, the Form 10-K that was filed on February 17, 2004, and the Form 10-K that SigmaTel filed February 8, 2005 covering the annual period ended December 31, 2004.

SigmaTel is a registered trademark of SigmaTel. All other products and brand names as they appear in this release are trademarks or registered trademarks of their respective holders. All specifications may be changed without notice.