Disclosed herein are methods and systems for encrypting communications using a secure element. An embodiment takes the form of a method including the steps of performing a key-exchange procedure with an endpoint via a voice-communication device to obtain a symmetric seed key for a secure voice session with the endpoint; generating first and second symmetric session keys for the secure voice session based on the obtained symmetric seed key; receiving outbound voice packets from the voice-communication device in connection with the secure voice session, each outbound voice packet including a header and an unencrypted payload; using a first symmetric encryption algorithm and the first symmetric session key, followed by a second symmetric encryption algorithm and the second symmetric session key to generate and output twice-encrypted outbound-voice-packet payloads to the voice-communication device for transmission to the endpoint in connection with the secure voice session.