VoIP calling issues over cellular data

VoIP calls dropping or breaking up over cellular data usually comes down to latency and jitter rather than raw bandwidth — you can have plenty of data speed and still get bad call quality if the connection is inconsistent moment to moment, which is common on cellular versus wired connections. If this is a business-critical need, a bonded connection (Peplink SpeedFusion) can smooth this out significantly better than a single cellular connection.