Symbols are prepared for transmission by representing each bit of the symbols by a cluster of consecutive bits, identical to the bit, in a transmission bit sequence. The collected traffic logs are stored in a computer such that the traffic logs can be replayed. The invention greatly simplifies the fluid injection apparatus used in extrusion systems, while giving more efficient absorption of thermal energy with a minimum of environmental contamination, and the ability to inject multiple streams into the extrusion systems. Enhancements may contain MIDI information, audio signal information, andor video signal information which may be played back in synchronicity with the recorded performance to provide an aural and visual aid to others playing-along who may have less musical experience.