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Real-time Virtual Appliance

High-Level Summary

This release contains improvements to telephony models for English and Spanish, and a number of bugfixes.

The following languages now support advanced punctuation: English (en), German (de), Spanish (es), French (fr), Dutch (nl) and Danish (da).

It is recommended that customers on previous releases upgrade to this version.

Important Notices

The legacy V1 API that the Real-time Virtual Appliance currently supports will be discontinued in a future release. We recommend that customers familiarise themselves with the configuration object as described in the Speech API Guide. Future notices will be provided to announce the end of life of the V1 API, and provide detailed instructions on migrations to the V2 API.

What's New

  • Improvements to the telephony models for English and Spanish

Issues Fixed

The following issues are addressed since the previous release:

Issue IDSummaryResolution Description
REQ-7268The internal 'reset' method can cause a server panicThis messages will now no longer be seen in the logs when services are restarted.
REQ-7461Memory leak affecting licensing containerA small memory leak affecting the licensing service has now been addressed.
REQ-9618Spurious warnings in rt worker log even though transcription is successfulThis has now been fixed. Warnings in the log like this: WARNING ([5.4.659~1450-2d99]:OutputArcForce() Partial word detected at end of utterance will no longer be seen.
REQ-11644Offline activation cannot generate deactivation codePreviously if you submitted the PUT/POST request for offlineactivation, any attempt to deactivate with a DELETE request failed; this has now been fixed.
REQ-12172RTA Speech API Guide link from /help is brokenThe link has now been fixed; it is possible to access the Speech API guide from https://${APPLIANCE_HOST}:8080/help/

Known Limitations

The following are known issues in this release:

Issue IDSummaryDetailed Description and Possible Workarounds
REQ-1409Proteus HCL with <unk> causes out of memory errorA custom dictionary list that contains the word '' causes the worker to crash.
REQ-7549Memory leak affecting gRPCThere is a small memory leak in the gRPC Python server (
REQ-10160Advanced punctuation for Spanish (es) does not contain inverted marks.Inverted marks [ ¿ ¡ ] are not currently available for Spanish advanced punctuation.
REQ-10627Double full stops when acronym is at the end of the sentenceIf there is an acronym at the end of the sentence, then a double full stop will be output, for example: "team G.B.."
REQ-11087Additional white space appearing before the very last end of sentence punctuation character.Its been observed that additional white space can occur before a full-stop '.' in some transcripts.
REQ-111353.2.0 introduced unwanted hesitations in transcripts.Due to changes in the way that training data is now ingested to improve the accuracy of spontaneous speech for English (en) there is a greater likelihood that hesitations will be included in the output transcrtips. We plan to support a hesitation filtering capability in a future release for customers that do not want to see hesitations on transcripts.
REQ-11792Speaker change token positioning is incorrectWe are aware of a consistent mis-placing of the speaker change token after the first word of the new speakers' sentence rather than before it.
REQ-11829No worker available in RTVA in unclean disconnectsIt is possible to get stuck in a cycle of receiving "job_error - No worker can be scheduled because the service is at capacity" messages if the connection was not closed cleanly.
REQ-12202High memory usage when using custom dictionaryIt has been observed that when using custom dictionary an additional 800-1700MB of memory is required (depending on the size of the wordlist used).

Supported Platforms

Virtual Appliance image (OVA) for installation on:

  • VMware ESXi 6.5+ or VMware Workstation Player.
  • VirtualBox 5.2+
  • Amazon EC2

See the Installation and Admin Guide for details on the minimum specifications for the VM. The maximum number of concurrent jobs (maxworkers) that you can run on a single appliance is 32.

Form Factors

There are four variants of the Real-time Virtual Appliance.

VariantImage SizeMax. Disk SpaceLanguages
mini16GB40GBen, de, es
midi27GB60GBen, de, es, fr, ko, ja, nl, pt
maxi45GB80GBen, de, es, fr, ko, ja, nl, pt, it, da, pl, ca, hi, ru, sv

Upgrade Path

Remove the license from your old appliance (see the Admin Guide), then re-import the new OVA and configure networking as per the Installation and Admin guide. You will need to re-apply the license code you have once the OVA has imported.


Upload the OVA to VMWare ESX, VMWare Workstation Player, or VirtualBox. See the Installation and Admin Guide for more information.