umonitor for linux uses more than expected CPU

Seeing this in top on Magnum:

1735357 sbbs 20 0 99900 7072 1748 S 13.2 0.1 431:53.04 umonitor

So on my BBS, thats 13.2% of an Intel(R) Xeon(R) D-2141I CPU @ 2.20GHz

And on EOTL:

2303058 bbs 20 0 305076 17228 4184 S 17.3 0.4 0:04.06 umonitor

Should umonitor be using so much CPU?

Is there an opportunity to optimise umonitor when its just sat in monitor mode (default start up)?