try initial sleep(4.0) then while sleep(0.1)

afsk/main.c

@@ -1405,8 +1405,10 @@ void get_tlm_fox() {
 /**/
 //      while ((millis() - sampleTime) < (unsigned int)samplePeriod)
      int startSleep = millis();	    
-      while ((millis() - sampleTime) < ((unsigned int)frameTime - 500))  // was 100
+     if ((millis() - sampleTime) < ((unsigned int)frameTime - 500))  // was 100
-        sleep(1.0); // 0.5);  // 25);
+        sleep(4.0); // 0.5);  // 25);  // initial period
+     while ((millis() - sampleTime) < ((unsigned int)frameTime - 500))  // was 100
+        sleep(0.1); // 0.5);  // 25);
 //        sleep((unsigned int)sleepTime);
 /**/