Have you confirmed with another receiver there are active voice (or what you refer to as "speech") transmissions that DSDPlus isn't decoding? Your screenshot looks like weak data to me
Keep an eye out in the console window for this when there are active voice transmissions
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You'll also want to keep an eye on your event log window. Active voice will be light green and past voice events will be a darker green
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This will log encrypted voice events like shown below but won't decrypt conversations
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