Possible Clues:

• Of 31 across? No, that's false
• False, soft, sweet and dialable, perhaps
• Sounds soft, sweet, soft and ringing, by the sound of it
• Soft sweet stuff, but it's not genuine
• Insincere
• Not for real
• Sham, not genuine or sincere
• Fake sweetheart, soft initially
• Insincere (Var.)
• Fake, misleading