Possible Clues:

• Tamper with gong — that's audible!
• Tinker's award for service announced
• Be nosy
• Interfere with gold or silver, we hear?
• Tamper with gold or silver, by the sound of it?
• Poke one's nose in locally for what one gets we hear if one can do 15 across
• Tinker needs a bit of metal as you might say?
• Get nosy
• Tamper with gong's sound
• Interfere with 11 down, by the sound of it