We've got a 4g router (landline gives us 1.2mbps tops!) and although our speeds are usually in the 20-40mbps range, 25 ping, 5 jitter, 0 loss range, I find that when we stress the internet with streaming we get increased jitter on the line which causes the conversations to distort.
To describe our setup, we have the 4g router, which then has another router connected to it. This other router has a VoIP phone adapter and is what we all connect to (I have stressed the 4g router while calling on the other router to see if it's a router problem, but still get the jitter).
I have setup QoS on the router to prioritise voice, and also bandwidth allocation to give the phone adapter 2mbps of bandwidth. I have also enabled a 'very high jitter' setting on the VoIP phone adapter.
The only things left I think are to work out how to drop the priority for streaming video, or get a better router to give VoIP better priority.
Is it worth investing in a new router (ours is a tplink bgn variety which isn't that new) or can someone suggest something else. Unfortunately we can't get fibre