Although it is possible to manage several channels using a single just:connect instance, all channels managed by the same just:connect must use the same time base. So if you have channels using a different time base (i.e. one channel SD and one channel 50 fps) you must use a separate just:connect for each time base.
To avoid excessive network traffic in a single application, just:connect can receive and send the preview proxy which is shown in the user interface only for the first active channel. Therefore we recommend to have a dedicated just:connect for each channel.