diff --git a/sleepyhead/SleepLib/loader_plugins/cms50f37_loader.cpp b/sleepyhead/SleepLib/loader_plugins/cms50f37_loader.cpp
index fc19388e..73033502 100644
--- a/sleepyhead/SleepLib/loader_plugins/cms50f37_loader.cpp
+++ b/sleepyhead/SleepLib/loader_plugins/cms50f37_loader.cpp
@@ -450,16 +450,16 @@ void CMS50F37Loader::processBytes(QByteArray bytes)
         }
 
         if (res == 0x09) {
-            msb = quint8(buffer.at(idx+1));
+            quint8 * buf = (unsigned char *)&buffer.data()[idx];
             // 9,80,e1,c4,ce,82  // cms50i data
-//            for (int i = 2, msb = buffer.at(idx+1); i < len; i++, msb>>= 1) {
-//                buffer[idx+i] = (buffer[idx+i] & 0x7f) | (msb & 0x01 ? 0x80 : 0);
-//            }
+            for (int i = 2, msb = buf[1]; i < len; i++, msb>>= 1) {
+                buf[i] = (buf[i] & 0x7f) | (msb & 0x01 ? 0x80 : 0);
+            }
 
-            quint16 pi = quint8(buffer.at(idx + 4)) | ((msb & 4) << 5) | (quint16(buffer.at(idx + 5)) << 8);
+            quint16 pi = buf[4] | buf[5] << 8;
 
-            pulse = quint8(buffer.at(idx+3)) | ((msb & 2 ) << 6);
-            quint8 spo2 = buffer.at(idx+2);
+            pulse = buf[3];
+            quint8 spo2 = buf[2];
 
             oxirec->append(((spo2 == 0) || (pulse == 0) || (pi == 0xfff6)) ? OxiRecord(0,0,0) : OxiRecord(pulse, spo2, pi));