Data connection issue when roaming


New member
Dec 21, 2016
Visit site
I have an intermittent problem with a one year old Samsung A5 (2016) dual SIM running 6.0.1 marshmallow. Data connection is intermittent and not related to location. Sometimes it will connect and sometimes it won't. I have a T-Mobile US SIM set up for roaming and a Singtel SIM. If I set it to the Singtel Sim it will work for a while and then drop out, possibly when the signal strength drops. It will then not reconnect until I switch to the T-Mobile SIM, wait for it to connect, then switch back. To make things worse, sometimes it also won't connect to the T-Mobile SIM for long periods (hours) which means I also can't restart the Singtel SIM.
Since both SIMS work, I don't think it is a setting problem. I got Singtel to replace the SIM but that didn't seem to help. It seems to me the problem started after a recent Android system update but I may be wrong. WiFi works fine.
My question is does this sound like a software or hardware problem? Could it be a bad App? Is there any way to run a diagnostic on the hardware?
Thanks for your help.