Troubleshooting Medialive

IF "Unable to assume role" or "Access denied":
  → Trust policy MUST include medialive.amazonaws.com
  → Action MUST include sts:AssumeRole AND sts:TagSession
IF input not found:
  → Input may have been deleted/recreated (new ID). Update channel config.
  → CDI inputs: both subnets MUST be provided even for SINGLE_PIPELINE
IF output destination unreachable:
  → Verify MediaPackage channel exists and ingest URL is current
  → If MediaPackage was recreated, ingest URL changed
IF resource limits:
  → Check Service Quotas for MediaLive in the region
IF 4K HEVC or other large-profile channel:
  → Provisioning takes longer than smaller channels. Start well in advance of any time-sensitive event and verify the channel reaches RUNNING before the event begins.

IF InputVideoFrameRate = 0:
  → Problem is upstream (source encoder, MediaConnect, network)
  → LOAD references/troubleshooting-mediaconnect.md
IF InputVideoFrameRate > 0 but OutputVideoFrameRate = 0:
  → Encoder overload. Check DroppedFrames metric.
  → Reduce ABR rungs, use shared encode outputs, lower complexity.
IF input loss behavior = EMIT_OUTPUT:
  → Channel outputs black on input loss BY DESIGN (keeps players alive)
  → This is correct for production. Check upstream for actual input loss.
IF HDR channel with SDR slate:
  → Slate MUST match channel colorspace/transfer function
  → SDR slates on HDR channels cause encoder errors

IF audio sync drift:
  → Check MediaConnect SourcePTSError (PTS discontinuities)
  → Verify SRT latency ≥4× RTT
  → For 8+ hour events: reboot encoders before (timecode drift accumulates)
IF missing audio:
  → Verify audio PID mapping in input settings matches source
  → Each language track needs separate audio selector
  → Check source codec is supported (PCM, AAC, AC3, EAC3, MPEG Audio)
IF inconsistent levels (program vs ads):
  → Enable ITU-R BS.1770 loudness normalization (BS.1770-4)
  → Target: -16 LKFS (streaming) or -24 LKFS (broadcast, ATSC A/85)

1. Source encoder: SCTE-35/SCTE-104 being inserted?
2. MediaConnect: passthrough (no config needed)
3. MediaLive (HLS): Scte35Behavior in M3u8Settings PER OUTPUT (NOT HlsGroupSettings level)
4. MediaLive (CMAF): Scte35Type = SCTE_35_WITHOUT_SEGMENTATION in CmafIngestGroupSettings
   → SCTE_35_ENHANCED MUST NOT be used (invalid enum)
5. MediaPackage: SCTE-35 in manifest (default if present in ingest)
   → MediaPackage v2 SCTE35_ENHANCED: CUE-IN event ID MUST match CUE-OUT event ID

IF pipeline locking not enabled:
  → Pipelines produce different sequence numbers → failover causes time jump
  → Enable pipeline locking (requires same source content on both pipelines)
IF file inputs (S3 MP4/TS):
  → No live timecode → standard pipeline locking won't work
  → Use InputClipSettings with zero-based approach
IF primary/secondary from different encode paths:
  → Pipeline locking not possible
  → Manual failover with session reinitialization required
  → MediaTailor SSAI also affected (sequence number mismatch)