A pilot at ANC's Lake Hood (PAHL) taxied without clearance after his microphone became disconnected but he thought he heard ANC Tower clearing him to taxi.

Narrative

Taxiing across a water lane at Lake Hood (Anchorage; Alaska -- Ted Stevens International Airport); without confirming communication with the Tower. I could hear and thought the Tower could hear me as I stated my intentions to taxi. I talked with the Tower just fine when I flew to Lake Hood about an hour earlier to get fuel and load my airplane. I switched from one radio to another thinking my first radio was not transmitting -- that did not help. I hear the Tower say something about hearing a squeal. At that point I decided to unplug and replug my headset. That's when I discovered one of the jacks had been slightly dislodged. Once replugged; I could communicate with the Tower but not before I taxied into a water lane that is available for takeoff and landing operations. That particular water lane was not active at the time (another water lane was active as I had previously used it for landing and I heard communication with the particular water lane was still active.) The contributing factor was when I was exiting the aircraft after landing; my seatbelt and foot got caught up in the headset cord dislodging one of the plug-in jacks -- it did not come out to indicate an obvious break in communication. Because the jack was slightly dislodged; I could receive but not transmit. A distraction occurred prior to taxiing: I fell in the water soaking an expensive cell phone and myself which I feel resulted in a loss of concentration. I learned always to establish connection with the Tower at a controlled airport prior to operations.