'post' data from conf file not sent

Hi

I have decoded the IR signal from a heater and written a conf file (copied below). However, when I send an IR signal with "irsend SEND_ONCE zehnderheating KEY_8", the 'post' pulse and space are missing; all other pulses and spaces are correct (see oscilloscope output at https://imgur.com/a/b06JM ; the measured length of the last long pulse matches ptrail, but post is missing). Run on a Raspberry Pi 3 with raspbian kernel version 4.9.59-v7+ and irsend version 0.9.4c. 

Any idea what could be the reason?

Al_



begin remote

  name          zehnderheating
  bits          8
  pre_data_bits 8
  flags         SPACE_ENC
#  eps           10
  aeps          68
  min_repeat    0

  zero          30   650
  one           30   830
# sequence: header plead pre_data pre data post post_data ptrail foot gap
  header        30  1000
  pre_data      0xB8
#  post          30   460
#  ptrail        30
  post          1000   460
  ptrail        300
# an arbitrary long space as nothing follows
  gap           100000

  frequency     455000
  duty_cycle    50

  begin codes
    KEY_0       0x0D   # switch heater off
    KEY_1       0x86
    KEY_2       0x95
    KEY_3       0xA0
    KEY_4       0xB3
    KEY_5       0xCA
    KEY_6       0xD9
    KEY_7       0xEC
    KEY_8       0xFF
  end codes

end remote

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