Avoid treating capture timing as microphone failure

gumble/gumbleopenal/stream.go

@@ -674,8 +674,9 @@ func (s *Stream) sourceRoutine(inputDevice *string) {
 			// available. PipeWire and PulseAudio do not guarantee that a Go
 			// ticker fires precisely on a capture-frame boundary.
 			hasMicInput := false
+			available := s.deviceSource.CapturedSamples()
 			var buff []byte
-			if s.deviceSource.CapturedSamples() >= uint32(frameSize) {
+			if available >= uint32(frameSize) {
 				buff = s.deviceSource.CaptureSamples(uint32(frameSize))
 			}
 			if len(buff) == sampleCount*2 {
@@ -700,7 +701,7 @@ func (s *Stream) sourceRoutine(inputDevice *string) {
 				} else {
 					s.processStereoSamples(int16Buffer, frameSize)
 				}
-			} else if !micFailed {
+			} else if available >= uint32(frameSize) && !micFailed {
 				micFailed = true
 				if s.errorFunc != nil {
 					s.errorFunc(ErrMic)