'nc' using ~100% CPU when transferring a FIFO file

On the server which is always connected I’m using this in a crontab:

@reboot nc -k -l 1234 < /tmp/fifo.fifo

On the client which is not always on the network or switched on I’m using this command:

nc -d $IP_OF_SERVER 1234 > /tmp/fifo.fifo & $SOME_COMMAND

The server listens always for a connection on the specified port (thanks to the -k parameter), the client just connects to the server when it needs to.

I’m using this for MPD and its FIFO visualizer. MPD runs on a remote host, but my MPD client (ncmpcpp) runs locally.

This is the important part of the ncmpcpp config on the local host:

mpd_host = "$IP_OF_SERVER"
visualizer_fifo_path = "/tmp/fifo.fifo"

This is the important part of the mpd config on the remote server:

audio_output {
        […]
        path    "/tmp/fifo.fifo"
        […]
}

Running the 'nc' command on my local machine seems to use a very high amount of resources … ~100% of my CPU performance.

Any ideas where the problem is? Or if this is normal and how I would improve this whole scenario?

Unfortunately it’s not possible to just specify a network-path for visualizer_fifo_path, like:

visualizer_fifo_path = "$http://IP_OF_SERVER:/tmp/fifo.fifo"

And it’s also not possible to mount the remote host via NFS and then use the FIFO which is mounted via NFS.