Hi Henry,
I would suggest your 3rd-party transcription provider should give our OPUS recording a try first. Genesys Cloud's own transcription in WEM consumes from the OPUS format as well, and our in-house testing shows no significant performance difference at all against the uncompressed formats like PCMU. Changing to PCMU will increase your storage needs, and depending on your recording intensity and retention period, could go above the fair use storage allocation threshold in the long run.
And of course, we would prefer you use our own transcription -- yes it requires a GC3 license, but you get the transcript as part of the recording playback UI, which is particularly useful if a supervisor is conducting QM evaluation all within Genesys Cloud. If you need to do custom Analytics on top of it, there are APIs available to get to the transcript as well.
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Daniel Ho
Product Line Manager – Recording and Quality Management, Genesys Cloud
Workforce Engagement Management (WEM)
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