The following spell from the 1E Unearthed Arcana might be a useful base for a new spell your character could look into researching. It used to come in handy for me with a grand master RBDM behind the screen.
Vocalize (Alteration)
Level: 2
Components: S, M
Range: Touch
Casting Time: 1 round
Duration: 5 rounds
Saving Throw: None
Area of Effect: One spell-casting creature
Explanation/Description: This spell allows the recipient to cast spells that normally require a verbal component without having to make a sound, so long as the casting of the subsequent spell(s) takes place entirely within the duration of the vocalize spell. This spell is of great use in situations where quiet is desired, or when the recipient is under the influence of a silence spell. The vocalize spell does not negate possible effects upon other vocal communication (a message spell could be cast from within an area of magical silence, but no information would be transmitted back to the caster). The spell does not negate the effect of silence, but merely offsets it for the purpose subsequent spell casting. If a spell cast by means of a vocalize spell has some audible effect, that sound will be masked for as long as the silence spell remains in force. The material component of this spell is a bell without a clapper, or else a jailbird's tongue.
A 3.0/3.5E version might look something like this, with descriptive text similar to the 1E version.
Vocalize
Transmutation
Level: Brd 2, Rgr 1, Sor/Wiz 2
Components: S, M
Casting Time: 1 standard action
Range: Touch
Target: Creature touched
Duration: 5 rounds
Saving Throw: None
Spell Resistance: Yes (harmless)