diff --git a/CHANGELOG.md b/CHANGELOG.md
index 09514e52..3c1d0bd3 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -24,6 +24,8 @@ will consitute of a breaking change warranting a new major release:
   A filesystem change via `prefSD` on bootup, can lead to the TLE not being read, even
   though it is there.
 - Added action cmd to read the currently stored TLE.
+- Both the `AcsController` and the `PwrController` now use the monotonic clock to calculate
+  the time difference.
 
 # [v7.4.0] 2023-11-30
 
diff --git a/mission/controller/PowerController.cpp b/mission/controller/PowerController.cpp
index f8a02c09..719ef507 100644
--- a/mission/controller/PowerController.cpp
+++ b/mission/controller/PowerController.cpp
@@ -158,6 +158,11 @@ ReturnValue_t PowerController::checkModeCommand(Mode_t mode, Submode_t submode,
 void PowerController::calculateStateOfCharge() {
   // get time
   Clock::getClockMonotonic(&now);
+  double timeDelta = 0.0;
+  if (now.tv_sec != 0 and oldTime.tv_sec != 0) {
+    timeDelta = timevalOperations::toDouble(now - oldTime);
+  }
+  oldTime = now;
 
   // update EPS HK values
   ReturnValue_t result = updateEpsData();
@@ -173,8 +178,6 @@ void PowerController::calculateStateOfCharge() {
         pwrCtrlCoreHk.setValidity(false, true);
       }
     }
-    // store time for next run
-    oldTime = now;
     return;
   }
 
@@ -195,12 +198,10 @@ void PowerController::calculateStateOfCharge() {
         pwrCtrlCoreHk.coulombCounterCharge.setValid(false);
       }
     }
-    // store time for next run
-    oldTime = now;
     return;
   }
 
-  result = calculateCoulombCounterCharge();
+  result = calculateCoulombCounterCharge(timeDelta);
   if (result != returnvalue::OK) {
     // notifying events have already been triggered
     {
@@ -215,9 +216,6 @@ void PowerController::calculateStateOfCharge() {
         pwrCtrlCoreHk.coulombCounterCharge.setValid(false);
       }
     }
-    // store time for next run
-    oldTime = now;
-    return;
   }
 
   // commit to dataset
@@ -231,8 +229,6 @@ void PowerController::calculateStateOfCharge() {
       pwrCtrlCoreHk.setValidity(true, true);
     }
   }
-  // store time for next run
-  oldTime = now;
 }
 
 void PowerController::watchStateOfCharge() {
@@ -285,17 +281,14 @@ ReturnValue_t PowerController::calculateOpenCircuitVoltageCharge() {
   return returnvalue::OK;
 }
 
-ReturnValue_t PowerController::calculateCoulombCounterCharge() {
-  double timeDiff = 0.0;
-  if (oldTime.tv_sec != 0) {
-    timeDiff = timevalOperations::toDouble(now - oldTime);
-  } else {
+ReturnValue_t PowerController::calculateCoulombCounterCharge(double timeDelta) {
+  if (timeDelta == 0.0) {
     return returnvalue::FAILED;
   }
-  if (timeDiff > maxAllowedTimeDiff) {
+  if (timeDelta > maxAllowedTimeDiff) {
     // should not be a permanent state so no spam protection required
-    triggerEvent(power::TIMEDELTA_OUT_OF_BOUNDS, static_cast<uint32_t>(timeDiff * 10));
-    sif::error << "Power Controller::Time delta too large for Coulomb Counter: " << timeDiff
+    triggerEvent(power::TIMEDELTA_OUT_OF_BOUNDS, static_cast<uint32_t>(timeDelta * 10));
+    sif::error << "Power Controller::Time delta too large for Coulomb Counter: " << timeDelta
                << std::endl;
     return returnvalue::FAILED;
   }
@@ -303,7 +296,7 @@ ReturnValue_t PowerController::calculateCoulombCounterCharge() {
     coulombCounterCharge = openCircuitVoltageCharge;
   } else {
     coulombCounterCharge =
-        coulombCounterCharge + iBat * CONVERT_FROM_MILLI * timeDiff * SECONDS_TO_HOURS;
+        coulombCounterCharge + iBat * CONVERT_FROM_MILLI * timeDelta * SECONDS_TO_HOURS;
     if (coulombCounterCharge >= coulombCounterChargeUpperThreshold) {
       coulombCounterCharge = coulombCounterChargeUpperThreshold;
     }
diff --git a/mission/controller/PowerController.h b/mission/controller/PowerController.h
index b7c3d1a0..6df60732 100644
--- a/mission/controller/PowerController.h
+++ b/mission/controller/PowerController.h
@@ -45,7 +45,7 @@ class PowerController : public ExtendedControllerBase, public ReceivesParameterM
   void calculateStateOfCharge();
   void watchStateOfCharge();
   ReturnValue_t calculateOpenCircuitVoltageCharge();
-  ReturnValue_t calculateCoulombCounterCharge();
+  ReturnValue_t calculateCoulombCounterCharge(double timeDelta);
   ReturnValue_t updateEpsData();
   float charge2stateOfCharge(float capacity, bool coulombCounter);
   ReturnValue_t lookUpTableOcvIdxFinder(float voltage, uint8_t& idx, bool paramCmd);
diff --git a/mission/controller/acs/AcsParameters.h b/mission/controller/acs/AcsParameters.h
index 598fecb3..80269d55 100644
--- a/mission/controller/acs/AcsParameters.h
+++ b/mission/controller/acs/AcsParameters.h
@@ -78,9 +78,9 @@ class AcsParameters : public HasParametersIF {
                                        {-0.007534, 1.253879, 0.006812},
                                        {-0.037072, 0.006812, 1.313158}};
 
-    float mgm02variance[3] = {pow(3.2e-7, 2), pow(3.2e-7, 2), pow(4.1e-7, 2)};
-    float mgm13variance[3] = {pow(1.5e-8, 2), pow(1.5e-8, 2), pow(1.5e-8, 2)};
-    float mgm4variance[3] = {pow(1.7e-6, 2), pow(1.7e-6, 2), pow(1.7e-6, 2)};
+    double mgm02variance[3] = {pow(3.2e-7, 2), pow(3.2e-7, 2), pow(4.1e-7, 2)};
+    double mgm13variance[3] = {pow(1.5e-8, 2), pow(1.5e-8, 2), pow(1.5e-8, 2)};
+    double mgm4variance[3] = {pow(1.7e-6, 2), pow(1.7e-6, 2), pow(1.7e-6, 2)};
     float mgmVectorFilterWeight = 0.85;
     float mgmDerivativeFilterWeight = 0.99;
     uint8_t useMgm4 = false;
@@ -790,10 +790,10 @@ class AcsParameters : public HasParametersIF {
 
     /* var = sigma^2, sigma = RND*sqrt(freq), following values are RND^2 and not var as freq is
      * assumed to be equal for the same class of sensors */
-    float gyr02variance[3] = {pow(4.6e-3, 2),   // RND_x = 3.0e-3 deg/s/sqrt(Hz) rms
+    double gyr02variance[3] = {pow(4.6e-3, 2),   // RND_x = 3.0e-3 deg/s/sqrt(Hz) rms
                               pow(4.6e-3, 2),   // RND_y = 3.0e-3 deg/s/sqrt(Hz) rms
                               pow(6.1e-3, 2)};  // RND_z = 4.3e-3 deg/s/sqrt(Hz) rms
-    float gyr13variance[3] = {pow(11e-3, 2), pow(11e-3, 2), pow(11e-3, 2)};
+    double gyr13variance[3] = {pow(11e-3, 2), pow(11e-3, 2), pow(11e-3, 2)};
     uint8_t preferAdis = false;
     float gyrFilterWeight = 0.6;
   } gyrHandlingParameters;
diff --git a/mission/controller/acs/SensorProcessing.cpp b/mission/controller/acs/SensorProcessing.cpp
index 0390d7f1..c454440a 100644
--- a/mission/controller/acs/SensorProcessing.cpp
+++ b/mission/controller/acs/SensorProcessing.cpp
@@ -15,13 +15,12 @@ void SensorProcessing::processMgm(const float *mgm0Value, bool mgm0valid, const
   // ------------------------------------------------
   double magIgrfModel[3] = {0.0, 0.0, 0.0};
   bool gpsValid = false;
-  if (gpsDataProcessed->source.value != acs::gps::Source::NONE) {
+  if (gpsDataProcessed->source.value != acs::GpsSource::NONE) {
+    // There seems to be a bug here, which causes the model vector to drift until infinity, if the
+    // model class is not initialized new every time. Works for now, but should be investigated.
     Igrf13Model igrf13;
     igrf13.schmidtNormalization();
     igrf13.updateCoeffGH(timeAbsolute);
-    // ToDo
-    // maybe put a condition here, to only update after a full day, this
-    // class function has around 700 steps to perform
     igrf13.magFieldComp(gpsDataProcessed->gdLongitude.value, gpsDataProcessed->gcLatitude.value,
                         gpsDataProcessed->altitude.value, timeAbsolute, magIgrfModel);
     gpsValid = true;