Tested. With dvbc anx b (using dvbc option) and atscc it has the same behaviour
Versions:
LibreELEC (community) Version: 8.0.0f-annexB
LibreELEC git: c3df916ccd7b06fb923e473f7b2c308501498ada
HTS Tvheadend 4.1.2459 ~ LibreELEC Tvh-addon v8.1.11
SSH output
[ 678.452137@3] AVL: avl6862_read_status: Level=32
[ 678.652618@3] AVL: avl6862_read_status: Level=32
[ 678.852421@3] AVL: avl6862_read_status: Level=32
[ 679.052360@3] AVL: avl6862_read_status: Level=32
[ 679.252485@3] AVL: avl6862_read_status: Level=32
[ 679.452502@3] AVL: avl6862_read_status: Level=32
[ 679.509686@2] AVL: avl6862_set_dvbmode: initing demod for delsys=1
[ 679.509869@2] i2c i2c-1: Load avl6862 firmware patch for DVB-C size=48320
[ 680.576569@3] AVL: avl6862_wait_demod_boot: status:1 ready_code:0x5aa57ff7
[ 680.602361@3] AVL: avl6862_wait_demod_boot: status:0 ready_code:0x5aa57ff7
[ 680.602763@3] i2c i2c-1: avl6862 patch ver 2.0 build 22219
[ 680.704824@3] R848: r848_set_params: delivery_system=2 frequency=507000000 symbol_rate=5360000 bandwidth_hz=6000000
[ 680.723636@2] R848: r848_set_params: R848_SetPllData for DVB-S OK!!!
[ 680.723652@2] R848: r848_set_params: R848_SetStandard=35
[ 680.723657@2] R848: r848_set_params: R848_SetFrequency=507000000 KHz
[ 680.723811@2] R848: R848_GetLockStatus: R848_GETLOCKSTATUS=0x3f
[ 680.723817@2] R848: r848_set_params: Tuner not Locked!
[ 680.751698@2] R848: R848_GetLockStatus: R848_GETLOCKSTATUS=0x3f
[ 680.751711@2] R848: r848_set_params: Tuner not Locked!
[ 680.781696@2] R848: R848_GetLockStatus: R848_GETLOCKSTATUS=0x3f
[ 680.781707@2] R848: r848_set_params: Tuner not Locked!
[ 680.811691@2] R848: R848_GetLockStatus: R848_GETLOCKSTATUS=0x3f
[ 680.811704@2] R848: r848_set_params: Tuner not Locked!
[ 680.841700@2] R848: R848_GetLockStatus: R848_GETLOCKSTATUS=0x3f
[ 680.841713@2] R848: r848_set_params: Tuner not Locked!
[ 680.872386@2] AVL: avl6862_read_status: Level=32
[ 680.873043@2] AVL: avl6862_read_status: Level=32
[ 680.917172@2] AVL: avl6862_read_status: Level=32
[ 680.967244@2] AVL: avl6862_read_status: Level=32
[ 681.017311@2] AVL: avl6862_read_status: Level=32
[ 681.067511@2] AVL: avl6862_read_status: Level=32
[ 681.072263@2] AVL: avl6862_read_status: Level=32
[ 681.117603@2] AVL: avl6862_read_status: Level=32
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Tvheadend output
Loglevel debug: enabled
2017-03-17 17:25:14.997 mpegts: mydvbc - adding mux Multiplex [onid:FFFF tsid:FFFF] in mydvbc to scan queue weight 5 flags 1000
2017-03-17 17:25:21.277 mpegts: mydvbc - adding mux 507MHz in mydvbc to scan queue weight 6 flags 4000
2017-03-17 17:25:21.284 mpegts: 507MHz in mydvbc - add raw service
2017-03-17 17:25:21.285 mpegts: 507MHz in mydvbc - tuning on Availink avl6862 #0 : DVB-C #0
2017-03-17 17:25:21.285 linuxdvb: Availink avl6862 #0 : DVB-C #0 - starting 507MHz in mydvbc
2017-03-17 17:25:22.479 mpegts: 507MHz in mydvbc - started
2017-03-17 17:25:22.479 epggrab: 507MHz in mydvbc - registering mux for OTA EPG
2017-03-17 17:25:22.509 mpegts: 507MHz in mydvbc - open PID 0012 (18) [20/0xac181a38]
2017-03-17 17:25:22.509 mpegts: 507MHz in mydvbc - open PID 0BBA (3002) [16/0xac182e68]
2017-03-17 17:25:22.509 mpegts: 507MHz in mydvbc - open PID 0BBB (3003) [16/0xac184298]
2017-03-17 17:25:22.509 mpegts: 507MHz in mydvbc - open PID 0039 (57) [16/0xac1856c8]
2017-03-17 17:25:22.509 mpegts: 507MHz in mydvbc - open PID 012B (299) [16/0xac186af8]
2017-03-17 17:25:22.509 mpegts: 507MHz in mydvbc - open PID 1FFB (8187) [20/0xac187f28]
2017-03-17 17:25:22.509 mpegts: 507MHz in mydvbc - open PID tables subscription [0042/0xac174e50]
2017-03-17 17:25:22.509 subscription: 0001: "scan" subscribing to mux "507MHz", weight: 6, adapter: "Availink avl6862 #0 : DVB-C #0", network: "mydvbc", service: "Raw PID Subscription"
2017-03-17 17:25:22.648 linuxdvb: Availink avl6862 #0 : DVB-C #0 - status FAINT (SIGNAL)
2017-03-17 17:25:27.442 mpegts: 507MHz in mydvbc - scan no data, failed
2017-03-17 17:25:27.442 subscription: 0001: "scan" unsubscribing
2017-03-17 17:25:27.442 mpegts: 507MHz in mydvbc - close PID tables subscription [0042/0xac174e50]
2017-03-17 17:25:27.442 mpegts: 507MHz in mydvbc - stopping mux
2017-03-17 17:25:27.442 linuxdvb: Availink avl6862 #0 : DVB-C #0 - stopping 507MHz in mydvbc
2017-03-17 17:25:27.442 mpegts: 507MHz in mydvbc - close PID 0012 (18) [20/0xac181a38]
2017-03-17 17:25:27.442 mpegts: 507MHz in mydvbc - close PID 0039 (57) [16/0xac1856c8]
2017-03-17 17:25:27.442 mpegts: 507MHz in mydvbc - close PID 012B (299) [16/0xac186af8]
2017-03-17 17:25:27.442 mpegts: 507MHz in mydvbc - close PID 0BBA (3002) [16/0xac182e68]
2017-03-17 17:25:27.442 mpegts: 507MHz in mydvbc - close PID 0BBB (3003) [16/0xac184298]
2017-03-17 17:25:27.442 mpegts: 507MHz in mydvbc - close PID 1FFB (8187) [20/0xac187f28]
2017-03-17 17:25:27.443 mpegts: mydvbc - removing mux 507MHz in mydvbc from scan queue
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Is it also returning infinite times this error only when either atsc or dvbc tuner gets enabled
[ 603.255042@3] R848: r848_init:
[ 606.252375@3] AVL: avl6862_read_status: Level=32
[ 606.452026@3] AVL: avl6862_read_status: Level=32
[ 606.652200@3] AVL: avl6862_read_status: Level=32
[ 606.852387@3] AVL: avl6862_read_status: Level=32
[ 607.052379@3] AVL: avl6862_read_status: Level=32
[ 607.252448@3] AVL: avl6862_read_status: Level=32
[ 607.452020@3] AVL: avl6862_read_status: Level=32
[ 607.652353@3] AVL: avl6862_read_status: Level=32