In your page script, add a command to query the receiver's current mute status and cache that result in an activity level variable. (this would be the value you store into tmpVariable from your loop. In this case, let's assume the variable is called mainMute and will contain either 'ON' or 'OFF'.

i.e. socket.write('MU?\r');

In your socket.onData() function, you will need to process the string returned and if it begins with "MU", you will cache the part past MU and store in your variable named mainMute.

Then, in your button script, do exactly what you are doing but reference a different variable.

if (mainMute === 'ON')
socket.write('MUOFF\r');
else
socket.write('MUON\r');

My module does something similar but in similar fashion. After writing a module for denon 3 times now, I've tried different approaches and found one that I really like. (See note about SJHart above)

I've spent many hours developing what I consider to be a robust solution which I am not prepared to make public domain at this time. I hope you can understand and appreciate that.

Please contact me @ yahoo or via RC Mail if you'd like to discuss further.