If a sink supports dynamic latency and the latency is adjusted downwards, there needs to be a rewind to ensure that the sink buffer doesn't contain more data than what is allowed by the new latency. This is because rewind requests can't be larger than the configured latency, and if there's more data than that in the buffer, a later rewind request may end up being too small.
The responsibility for issuing the rewind request is currently on the sink implementor. I don't think that's necessary, so I think it would be better to issue the rewind request in the core code.
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