A person receiving a Voice over IP call, such as a call center agent, remotely controls media settings on a caller's multimedia terminal device functioning as a telephone terminal device. In some embodiments, the call center agent may remotely control media settings by entering a DTMF (dual tone multi-frequency) sequence from the telephone keypad. The DTMF sequence may be recognized by a gateway through which an Internet-to-PSTN call is made, stripped out of the audio stream and sent to the caller's multimedia terminal device in a separate command message through the Internet, or the DTMF sequence may be encoded into packets along with the voice information for detection and translation into a command message by software at the caller's terminal device. In pure VoIP applications, command packets may be sent directly. When a command message is received at the caller's terminal device, software on the end user computer makes the corresponding media setting changes without requiring any intervention on the part of the caller.