Possible Clues:

• Express Takeaway for Mum perhaps?
• Sound out perhaps expression to the French by boat
• Failing to drink round by bar that's silent
• Lacking strong grip, perhaps, keeping nothing quiet?
• Mum solves cryptic when eating dessert?
• Totally innocent about love, so unable to speak
• 'If the invoice was, there'd be nothing more than in it. (That's a dumb one!) (9)'
• Mum has no opinion?
• You'll get nothing out of anyone like this, by the sound of it
• Unsound, in a manner of speaking