MaxScale received fatal signal 11

Hi,

I'm using MaxScale proxy on more than 40 boxes and now I got a weird error on one of the box.
Opp
2015-06-15 12:30:05 Error : Write failed, dcb is closed.
2015-06-15 12:30:05 Fatal: MaxScale received fatal signal 11. Attempting backtrace.
2015-06-15 12:30:05 /usr/local/mariadb-maxscale/bin/maxscale() [0x52189c]
2015-06-15 12:30:05 /lib64/libpthread.so.0(+0xf710) [0x7fa206689710]
2015-06-15 12:30:05 /usr/local/mariadb-maxscale/bin/maxscale(spinlock_acquire+0x1d) [0x521569]
2015-06-15 12:30:05 /usr/local/mariadb-maxscale/modules/libMySQLBackend.so(+0x44a3) [0x7fa1e816b4a3]
2015-06-15 12:30:05 /usr/local/mariadb-maxscale/bin/maxscale(dcb_close+0x332) [0x527f43]
2015-06-15 12:30:05 /usr/local/mariadb-maxscale/modules/libreadconnroute.so(+0x20c8) [0x7fa2005ea0c8]
2015-06-15 12:30:05 /usr/local/mariadb-maxscale/modules/libMySQLClient.so(+0x4b9b) [0x7fa1eaf81b9b]
2015-06-15 12:30:05 /usr/local/mariadb-maxscale/bin/maxscale(dcb_close+0x332) [0x527f43]
2015-06-15 12:30:05 /usr/local/mariadb-maxscale/modules/libMySQLClient.so(+0x3970) [0x7fa1eaf80970]
2015-06-15 12:30:05 /usr/local/mariadb-maxscale/bin/maxscale() [0x533ac1]
2015-06-15 12:30:05 /usr/local/mariadb-maxscale/bin/maxscale(poll_waitevents+0x634) [0x533380]
2015-06-15 12:30:05 /lib64/libpthread.so.0(+0x79d1) [0x7fa2066819d1]
2015-06-15 12:30:05 /lib64/libc.so.6(clone+0x6d) [0x7fa204ff286d]

After I restarted MaxScale everything is fine again, but I don't know what caused the problem.
I don't use the read-write splitting I only use the "read connection router" ability.

If you need anything else just let me know.
Tibi