Sorry to perhaps hijack this thread but it could explain the users problem. When I compare the two results from libdvb I only see the video and audio pids change of note. The tsid changes but that is for all frequencies so that probably can be ignored.
Code
[BBC FOUR HD]
SERVICE_ID = 18048
NETWORK_ID = 9018
TRANSPORT_ID = 16522
VIDEO_PID = 6701
AUDIO_PID = 6702 6706
PID_0b = 7302
PID_06 = 6705
PID_05 = 7108
FREQUENCY = 634000000
MODULATION = QAM/256
BANDWIDTH_HZ = 8000000
INVERSION = OFF
CODE_RATE_HP = 2/3
CODE_RATE_LP = AUTO
GUARD_INTERVAL = 1/128
TRANSMISSION_MODE = 32K
HIERARCHY = NONE
DELIVERY_SYSTEM = DVBT2
STREAM_ID = 0
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and
Code
[BBC FOUR HD]
SERVICE_ID = 18048
NETWORK_ID = 9018
TRANSPORT_ID = 4170
PID_0b = 7303 7302
PID_05 = 7109
FREQUENCY = 634000000
MODULATION = QAM/256
BANDWIDTH_HZ = 8000000
INVERSION = OFF
CODE_RATE_HP = 2/3
CODE_RATE_LP = AUTO
GUARD_INTERVAL = 1/128
TRANSMISSION_MODE = 32K
HIERARCHY = NONE
DELIVERY_SYSTEM = DVBT2
STREAM_ID = 0
Display More