The phone tree is a maze with the structure of the edges and vertices of a dodecahedron. In it, there is interfering crosstalk from another caller which can occasionally force the solver into distressing holds. The three answers may be found in any order.
The interfering caller is a wumpus, as in "Hunt the Wumpus", an old computer game typically built in a dodecahedral maze. WUMPUS is clued by the first letters of "West Utumean Metaphysical Plant Unlimited Services". The wumpus is located at one (random) node of the maze. Being within two links of the wumpus causes you to hear "crosstalk", of varying volume depending on distance. Walking onto the wumpus puts you in a hold, where you've been bumped by the wumpus. However, if you locate the wumpus and press # before entering the node (as instructed in the introduction), you bump the wumpus instead and hear a long rant. He then re-locates. Bumping the wumpus three times results in his final rant in which he tells you that the answer is ABSOLUTE AUTHORITY.
When you are bumped, you hear one of three different hold messages followed by "The Song That Never Ends". Each provides instructions for escaping the hold: you must either insert a coin, demonstrate military priority, or hang up and call back from an American Samoa number. The solver must use phone-phreaking techniques which simulate meeting these challenges (or, conceivably, satify them legitimately, if you happen to calling from a payphone, a phone with an Autovon keypad, or a phone with an American Samoa number).
Each correctly answered challenge will then play DTMF tones:
Ordering by the number of initial # tones and catenating the digits gives 9780679781295, recognizable as an ISBN-13 by its form (or by Googling). It corresponds to the book FLOOD, another answer to the puzzle.
The third answer is based on the menu titles, menu structure, and the four voices speaking the menus. The map below is colored to show each of the voices. There is only one way to traverse the maze in such a way as to pass through every menu spoken by the first voice, then every menu spoken by another, and so forth, starting from the entrance. This path is shown in bold and is the solution path.
The menus in path order (including the menu selection number) are:
Index into the name of each menu by the key you pressed to get there. Changes in voice are word breaks. These indices give YAKKO SPELLS SANTA TUNE, cluing THE FIRST NOEL.
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