rostopic echo gets no data but node does

This is how my setup looks like - desktop computer - odroid xu4 (arm computer) I tried running the master on both computers and I export the the ROS_IP and ROS_MASTER_URI like that: - oroid: export ROS_IP=odroid_IP and export ROS_MASTER_URI=http://desktop_IP:11311 - desktop: export ROS_IP=desktop_IP and export ROS_MASTER_URI=http://desktop_IP:11311 I publish image data from the odroid and I get the data on the desktop. I process the image data on the desktop computer and publish a std_msg::Float32 (lets call the topic "duration") message with a time stamp. So good so far... Now here's the problem: When I try plotting the "duration" topic with rqt or try rostopic echo "duration", I don't get any data. But when I write a small python script and subscribe to the topic "duration" and print the data on the console, it works just fine... It also works if I run everything on the desktop computer (camera attached to the desktop) and run rqt or rostopic echo. Any help would be appreciated Thanks!