No datalink during SITL using jMAVSim

I’m having some problems with datalink on localhost using jMAVSim.
The environment boots corretly however as soon as I issue a command I get the

WARN [commander] Failsafe enabled: no datalink

and most of the times I do not regain the control of the simulation. The drone is unresponsive.
And I have to shutdown and restart. Unfortunately I’m now starting to understand the system and I don’t know how to debug this situation. Please help!

I’m using the latest firmware using the windows toolchain.

INFO  [simulator] Simulator connected on TCP port 4560.
Init MAVLink
INFO  [commander] LED: open /dev/led0 failed (22)
INFO  [init] Mixer: etc/mixers/quad_w.main.mix on /dev/pwm_output0
INFO  [mavlink] mode: Normal, data rate: 4000000 B/s on udp port 18570 remote port 14550
INFO  [mavlink] mode: Onboard, data rate: 4000000 B/s on udp port 14580 remote port 14540
INFO  [ecl/EKF] 964000: EKF aligned, (baro height, IMU buf: 22, OBS buf: 14)
INFO  [ecl/EKF] 964000: reset position to last known position
INFO  [ecl/EKF] 964000: reset velocity to zero
INFO  [logger] logger started (mode=all)
INFO  [logger] Start file log (type: full)
INFO  [logger] Opened full log file: ./log/2020-03-18/19_28_44.ulg
INFO  [mavlink] MAVLink only on localhost (set param MAV_BROADCAST = 1 to enable network)
INFO  [px4] Startup script returned successfully
pxh> INFO  [ecl/EKF] 9892000: GPS checks passed (WGS-84 origin set)
INFO  [ecl/EKF] 14420000: reset position to GPS
INFO  [ecl/EKF] 14420000: reset velocity to GPS
INFO  [ecl/EKF] 14420000: commencing GPS fusion

pxh> commander takeoff
pxh> INFO  [commander] Takeoff detected
WARN  [commander] Failsafe enabled: no datalink
INFO  [navigator] RTL HOME activated
INFO  [navigator] RTL: landing at home position.
INFO  [navigator] RTL: climb to 499 m (10 m above destination)
INFO  [navigator] RTL: return at 499 m (10 m above destination)
INFO  [navigator] RTL: land at destination
INFO  [commander] Landing detected
INFO  [logger] closed logfile, bytes written: 3603148