V3 Audio Channels Guide
We have seen some customers experiencing interference with the radios on the Analogue channels. We have made some changes to this framework to help address this problem.
If the channel name has a "-T" in the name, it means that tone filtering or CTCSS filtering is enabled on this channel.
Analogue Channel Selection Information.
MSNZ-T-L
MSNZ-T-M
MSNZ-T-H
These channels are all the same channel, with different levels of interference filtering. It will depend on the kind of interference you are getting and what works best for you; it will take a little trial and error to get the right filtering.