How to Resolve Audio Sync Related Issues - NTP Sync Issues
How to resolve Audio Sync or delay related Issues on Control4 digital audio devices
Connect to the audioserver (usually main controller) and all audioclient (output devices) through SSH using Putty
type: killall ntpd; reboot on each device.
Technical Support Bulletin
Product: All audio decoding devices
Software Affected: 1.6.0 to Current
Affects: All Primary Controllers, Speaker Points, Touch panels, as well as any other audio decoding output.
Synchronized Audio playback – Audio playback in multiple rooms is now synchronized based on NTP (Network Time Protocol), a client/server protocol used to synchronize clocks on separate devices within microseconds. The controller running Director will become synchronized with an external NTP server found on the Internet. All other Control4® devices will synchronize their clocks to Director’s clock. The synchronization process on the individual device may take up to an hour to complete after the device has booted up. After the synchronization process is complete, the audio playback in those zones will be fully synchronized.
To check if the device’s NTP client is out of sync with the Director controller’s NTP client, open up ComposerPro, go to “tools,” next select “System Diagnostics,” Next select “System Info” (it takes a minute or two to load all the devices). Click on the “+” symbol next to the affected Controller, and then click on the NTP client. The offset is the number of microseconds the device is out of sync with the director
The closer to 0 the more in sync the device is to the director.
If the offset is a large number it will be audibly out of sync. Also if the offset is a perfect 0.000 then it is not able to connect to the Director’s NTP server.
The Director controller’s ntp list is a little different in that it should show connections to internet time servers.
If it does not show any servers then the directors NTPD is not working.
If this is the case, try rebooting all of the devices which are out of sync.
If the director is not showing any server connections reboot the Director controller.
If that does not resolve the issue, then the NTPD process on the audio decoding devices as well as the Director controller need to be restarted.
Please see below for instructions.
1. Log into the controller using the terminal application "Putty" via an SSH connection.
(See KB 448 for instructions to SSH into the controller)
2. Use the kill all command to restart the ntpd server. killall ntpd
3. Reboot the device again with the reboot command.
4. Repeat steps 1 and 2 for each device that is out of sync, also to the director if it is not connected to any servers.
The synchronization process on the individual device may take up to an hour to complete after a reboot, update, or by typing killall -9 ntpd.
You can check the progress of the synchronization by checking the offset either by looking at the system info as stated above, or in putty with the ntpq -p command.