You're not wrong Jabez. TTT does indeed keep forcing the 1050 into 6.1 mode if you have the 6th speaker switched to ON. Without the speaker switched on you get the aforementioned dropouts. It is possible to switch 6.1 off but it only seems to last until there is some 6th speaker action at whihc point it mutes for a quarter of a second and switches 6.1 on. Looks like I'll need to get a 6th speaker now. Not very happy with this situation