Variable-length codes (e.g. Huffman codes) are commonly employed to minimize the average codeword length for noiseless encoding of discrete sources. Upon transmission over noisy channels, conflicting views note that such codes "tend to be self-synchronizing" and suffer from the "catastrophic effect of the error's propagation". Maxted and Robinson (1985) used a state model to describe the error recovery of the decoder. The present paper extends their results in several ways.