I have been attempting the last few days to play GTA V with a family member online. I purchased two copies of Xbox Live yesterday and created the two accounts with no issues.

What's happening --

Xbox 1: An older style xbox 360 with a USB wireless adapter.

Xbox 2: A newer style xbox 360 with the built in wireless.

Both Xboxes when performing when testing Xbox Live connection succeed without fail. However, when I connect to Xbox Live on either device and attempt to access GTA Online, they will periodically disconnect citing error 8015190E as the reason for the disconnection. No other devices ever lose connection to wireless and it appears that the Xbox's themselves also are not losing connection as the Xbox Live connection test has never failed.

Solutions I have tried --

• Clearing the cache on both devices, this achieved no noticeable difference and the issue persisted.
• My router supports uPnP, there doesn't appear to be any NAT related issues.
• I attempted to port forward the ports that the console uses, this did produce some recognisable progress in that Xbox 1 was able to remain connected for much longer before it was disconnected (but it would still disconnect). My router ( Technicolor TG797n v3 ) would not allow me to open the same ports for multiple IPs, (I don't even know if that's a thing anyway), leaving Xbox 2 with frequent disconnects.
• Reinstalling the Xbox update as suggested on a different reddit post. No difference was noted here.

Xbox Support online states that the error may mean:

• There's a temporary problem with the Xbox Live service.
• Your Xbox Live account has been temporarily blocked because the system detected suspicious activity.
• The profile stored on your Xbox 360 console is corrupt.
• Another profile has signed in.

As the accounts were made yesterday is it possible that either of them have been blocked or corrupt? I assume Xbox Live's services are running fine and no other profile has signed in to caused the error.

Any assistance with this error would be much appreciated.