m16 R2, BT mouse intermittently lagging when using BT headset

Hey  guys,

Recently purchased an m16 R2, works really well and love it, using it most of the time with a Logitect Bluetooth keyboard and mouse.  However just recently also bought a set of Dell Bluetooth headphones (had bonus $ to spend!).  I am finding that for around 5 seconds every 30 seconds the mouse lags by half a second or so and is very jittery, then back to normal.  Have seen that updates to the bluetooth driver should fix it which I have done, no change, all works perfectly until I star listening to music.  I have also gone through all updates to makes all are there and everything is current.

Any clues?