99. Trouble Shootings

Screen displayed on downlink

Receiving...（Blue）

The downlink has been successfully created and is waiting for a connection.

Input is inactive（Red）

The downlink has not been created properly and is not accepting connections. Check the source properties for proper receiver slot source settings.

This screen is also displayed when the user is not logged in with SRC-Link to begin with. In OBS Studio, go to the “Tools” menu -> “SRC-Link Settings” and click the “Login” button to log in.

Not enough ports（Red）

All ports in the port range have been used up and there are no more ports available for allocation.

Expand the port range in the “Tools” menu -> “SRC-Link Settings” in OBS Studio.

Also, do not forget to open the added ports on your NAT router or FW.

It is not an error to check if a port is open or not. The port check functionality is planned to be implemented, but it is incomplete and has not been implemented yet.

Guests will be on standby, but will not be active when assigned to a slot (no clean-feed is incoming)

If the guest is in standby and a screenshot is displayed in the SRC-Link Control Panel, but the clean-feed does not reach OBS Studio, check that the port is open on the NAT router or FW for the port range set in the host SRC-Link.

If the port cannot be opened, you should consider Deploying a Relay Server. If that is not possible, your environment will not allow you to receive clean-feeds.

Periodic clean-feed interruptions.

If you host with a free plan, there is a continuous receiving time limit. If the time limit is exceeded, the slot is returned to standby and a 5-minute cooldown occurs, after which it becomes active again.

It can be immediately resumed by manually performing an inactive -> active operation, but this is the specification as such.

This limitation is removed when you subscribe to a paid subscription. Also, if the guest side subscribes to a paid subscription, the continuous receiving time limit will be removed for that guest.

Guests are not on standby.

The uplink is initially set to interlock with the “virtual Cam” in OBS Studio, so please start the Virtual Cam. This specification is introduced to prevent accidents in which videos are unexpectedly sent to the host.

Start the Virtual Cam when it is ready to send video.

Other interlock functions can be selected from “Streaming”, “Recording”, “Streaming or Recording”, and “Always ON”.

Please note that “Always ON” starts transmission immediately after OBS Studio is launched.

Stream is unstable

If the stream is unstable, make the same adjustments as for SRT at the host.

Latency Tuning (SRT)

The recommended SRT latency is about 2.5 times the round-trip time (ping) For example, if the ping between guest and host is 50 ms, set it to 125 ms.

Increasing latency helps stabilize the stream, but increases latency instead. It can take more than 1,000 milliseconds to set up, especially if the connection is over a mobile line where line conditions are relatively worse.

Overall Settings

1. Open OBS Studio “Tools” menu -> “SRC-Link Settings”.
2. Set the latency in milliseconds in “Latency.”
3. Click “OK” to close and all downlinks will apply. Any downlinks where a member was active at this time will be reconnected with the new settings.

Individual downlink settings

1. Open the source properties of the downlink source and check the “Advanced” checkbox
2. Set latency to “Latency milliseconds
3. Click “OK” to close the properties and the downlink will apply. If the member is active at this time, the reconnection will occur with the new settings.

Individual member settings

Latency can be set for each member in the SRC-Link Control Panel (from SRT-Link Control Panel ver. 0.5.4)

1. Open the Host menu of the SRC-Link Control Panel
2. Select the target receiver and click on the member.
3. Set the latency in the Edit Member form.
4. Click “Save” to apply the latency to the member. If the member is active at this time, reconnection will occur with the new settings.

Individual settings take precedence over the overall settings. In particular, the per-member setting has the highest priority.

Set the same value for both the host and the guest, but SRC-Link will automatically set the value for the guest as well.

Network buffer tuning

Tuning the network buffer on the OBS Studio side can be expected to stabilize the stream in environments where line speeds are unstable. Of course, the more you increase the buffer size, the more it will affect latency.

Can only be set on the host side.

Overall setting

1. Open OBS Studio “Tools” menu -> “SRC-Link Settings”.
2. Check the box for “Advanced.”
3. Set the buffer size in megabytes in “Network Buffer”.
4. Click “OK” to close the properties and the downlink will apply. If the member is active at this time, the reconnection will occur with the new settings.

Individual downlink settings

1. Open the source properties of the downlink source and check the “Advanced” checkbox
2. Set the buffer size in megabytes in “Buffer”.
3. Click “OK” to close the properties and the downlink will apply. If the member is active at this time, the reconnection will occur with the new settings.

Host and guest are in the same LAN

SRC-Link can also be connected over a LAN. Normally, if the host and guest have the same public IP, the SRC-Link Control Panel will assume that they are on the same network and make the LAN connection. If you wish to force a LAN connection for network configuration reasons, check the “Prefer LAN connection” checkbox in Edit Member Form.

If the host PC has more than one local IP, select “Private IP for LAN connection” in the SRC-Link settings. The selected IP address will be used for the guest connection.