If you are rewinding and/or fast forwarding while listening, then you are by definition not in a hypnotic trance. Since you can only benefit from hypnosis by being in a trance, we purposely did not include a rewind or fast forward feature. The rewind button in the app will rewind all the way to the beginning, in case you'd like to start over.
If your mind wanders and you miss some of the voice audio, that's perfectly fine. Rest assured your subconscious mind is still listening and you are still receiving benefit.
To skip the audio instructions, you can disable the Audio Instructions switch in the Settings tab.