Speech language models process audio much faster than text, so they store a large memory of past sounds. This memory, called a key-value cache, grows huge with long audio and slows down generation while using a lot of memory.
The researchers developed C3, which organizes the cache into clusters and lets parts of the model compete for access to the most useful sections. They tested it on speech recognition, translation, and summarization using several different speech language models.
Under tight memory limits, C3 beat all other cache-reduction methods. On one difficult task, it cut the word error rate from 180.94% to 7.07%, showing that smart retrieval can make long-form speech processing both accurate and efficient.
