Sennheiser SYSTEM 2015 Instructions For Use Manual page 31

Switching between the channels
CHAN Via the "CHAN" menu, you can switch between the released channels. This
can be necessary when the selected channel is subject to interference.
With the 2015 System, a transmitter can be received by several receivers
on the same frequency. In this case, it may be necessary to switch to a chan-
nel that is released on all receivers.
Always set the transmitter and the receiver(s) of a transmission link to the
same channel. For multi-channel operation, only use the released channels
in one channel bank and, if possible, only use the channel banks "1" to "8"
since these accommodate fixed preset frequencies which are intermodula-
tion-free.
Exiting the operating menu
EXIT
Via the "EXIT" menu, you can exit the operating menu and return to the
standard display.
83