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voice class dualtone-detect-params 1
!
voice class custom-cptone CT
 dualtone disconnect
  frequency 425
  cadence 350 350
!
voice-port 1/1
 supervisory disconnect dualtone mid-call
 supervisory custom-cptone CT
 supervisory dualtone-detect-params 1
 no battery-reversal
 dial-type pulse
 disc_pi_off
 no vad
 no comfort-noise
 cptone RU
 timeouts call-disconnect 2
 timeouts wait-release 5
 timing guard-out 500
 connection plar 722491
 description FXO
!