Clearwire LLC (Nasdaq: CLWR) CEO Bill Morrow unexpectedly resigned Thursday, just two years after he joined as head of the troubled WiMax provider.

The Kirkland, Wash.-based operator put out a statement Thursday afternoon saying that Morrow had stepped down for "personal reasons." Morrow was the operator's second CEO, replacing Ben Wolff in the position on March 9, 2009.

The company also noted that Mike Sievert, chief commercial officer, and Kevin Hart, CIO, are leaving the company. Both are said to be leaving for other opportunities.

Chairman John Stanton will step in as interim CEO. Erik Prusch, Clearwire’s CFO, has been promoted to the new position of chief operating officer (COO) and will be responsible for the company’s day-to-day operations. Hope Cochran, Clearwire’s senior vice president and treasurer, has moved up to the position of CFO. The company has appointed a search committee, chaired by board member Dennis Hersch, to lead the hiring process for a new CEO.

Why this matters
Clearwire is in the midst of a dispute over wholesale pricing with Sprint Corp. (NYSE: S), its key partner and majority owner. Sprint CEO, Dan Hesse made it clear this week that -- although he expects Clearwire to remain part of its 4G service -- the CDMA operator isn't locked into using Clearwire as its only possible wholesale partner for next-generation wireless. Both Hesse and Clearwire, however, say they expect the dispute to be resolved soon.

For more
Read about Morrow's time at Clearwire below:

• Clearwire Cuts as It Hunts for Funding
  
• CTIA 2010: Hesse – LTE Will Be Bigger But We Are First
  
• Clearwire Swaps Out CEO
  
  

— Dan Jones, Site Editor, Light Reading Mobile