Due to a lack of pa_channel_map::&operator==() the code does a memcmp on
the cached m_channelMap to the new version in the update to see if our cache needs
updating.

As our struct starts of uninitialised, vagrlind prints a correct warning
about comparing uninitialised data. However, given our garbage data is
unlikely to match the update, it's not a bug that has a lot of impact.

valgrind plasmashell is quieter