No picture in the studio: the checklist

When no picture arrives in the studio, it is almost always a setting in the sending app: it sends RTMP instead of SRT, the address is wrong, or a passphrase is set. Go through the list from top to bottom; the most common causes come first.

Whether an input is connected you see in the studio on the “Eingänge” (inputs) tab. Every input says “Verbunden” (connected) or “Kein Signal” (no signal) there.

1. The app sends RTMP instead of SRT

Your studio accepts sources over SRT. Many apps and encoders are set to RTMP out of the box, because the platforms expect that. Change the protocol to SRT. An address of your studio always begins with srt://.

2. Address or stream ID are wrong

Every input has its own address in the form srt://<host>:<port>?streamid=<id>. Copy it from the “Eingänge” tab and do not type it. One missing character in the stream ID is enough, and the connection is refused.

Some apps want host, port and stream ID in separate fields. Then you take the address apart: the part after srt:// up to the colon is the host, the number after it the port, the part after streamid= the stream ID.

3. The app is set to “Listener”

The studio waits for the connection; it is the SRT listener. Your app has to set up the connection, that is, work in “Caller” mode. If both sides are set to listener, both wait, and nothing happens. Many apps have no setting of their own for this and are callers as soon as you enter an address.

4. A passphrase is set

The studio accepts SRT without encryption. The field for passphrase or encryption in your app stays empty. With a passphrase the studio cannot accept your stream.

5. The app sends another codec

The studio accepts H.264 or H.265 (HEVC) as picture and AAC as sound. If your app is set to another format, set the video codec to H.264 or H.265 and the sound to AAC. Which values have proved themselves is in Encoder settings.

6. The network blocks UDP

SRT runs over UDP. Many hotel, company and public Wi-Fi networks block or throttle that. The quick test: switch off Wi-Fi on the phone and send over mobile data. If the picture arrives then, it is the network. More on that in SRT on hotel or company Wi-Fi.

7. The studio is not running

An input only accepts while your studio is started. Two cases come up often:

• You have set up the app but not started the studio yet.
• The studio was ended automatically. That happens when it is not on air and has not been touched for 60 minutes, for example during a long setup.

Start the studio and let the app reconnect. On a day that is already paid for, starting again costs nothing.

8. More sources than inputs

You set the number of inputs on the “Eingänge” tab before you start the studio. While it runs, the number cannot be changed. If you have set up two inputs and want to connect a third camera, there is no address for it. End the studio, raise the number and start it again.

9. Two devices use the same address

An address belongs to one input, and an input accepts one source. As long as the first device is connected, a second one with the same address is refused. That happens easily when you have copied a setting from one phone to the other, or when a forgotten encoder is still running on a computer. Give every device the address of its own input.

When it says “Verbunden” but no picture is to be seen

Then the connection is fine, and you look elsewhere:

• Is the source on program or preview? A scene is an input. Click it to put it on preview.
• The preview in the browser is a control picture with only a few pictures per second.
• Is the app really sending a picture, or is the camera paused or covered in the app?

In short

Read on

• The picture stutters or breaks into blocks
• No sound from a source