# SCTE-35 limitations
<a name="scte-35-limitations"></a>

Limitations to SCTE-35 support are as follows:
+ You can either specify insertion points using ESAM XML or pass through SCTE-35 messages from the input. You can't do both.
+ AWS Elemental MediaConvert supports only time\$1signal messages, not splice\$1insert messages.
+ The service inserts SCTE-35 messages only into the following outputs: 
  + Outputs in **File group** output groups with **MPEG-2 Transport Stream** set for **Container**. 

    Set the container for each output under **Output settings**, **Container**.
  + Outputs in **DASH ISO** output groups.
  + Outputs in **Apple HLS** output groups.
  + Outputs in **CMAF** output groups.
+ The service forces Instantaneous Decoder Refresh (IDR) frames at the insertion points specified in your ESAM XML document for the following output codecs: MPEG-2, MPEG-4 AVC (H.264), or HEVC (H.265). 

  In the [MediaConvert console](https://console.aws.amazon.com/mediaconvert/), go to **Encoding settings**, **Video**, and then set the codec for each output in the **Video codec** section.
+ **DASH ISO** and **CMAF DASH** output groups only support single-period manifest outputs.