In a Symphony chat, users have the ability to disable their input (Figure 1):
Figure 1 Disable input
Disabling input prevents the user from sending any messages, chimes or attachments in that specific chat (Figure 2):
Figure 2 Input disabled
A user may choose to do this to prevent themselves accidentally sending messages in a room they don't want to, for example very large, or high-profile rooms.
If a user wishes to re-enable input, simply click the Input disabled icon again and the block on sending messages, chimes or attachments will be removed (Figure 3):
Figure 3 Enable input