diff --git a/devlib/instrument/acmecape.py b/devlib/instrument/acmecape.py
index 0d843a4..cc47d6d 100644
--- a/devlib/instrument/acmecape.py
+++ b/devlib/instrument/acmecape.py
@@ -97,7 +97,7 @@ class AcmeCapeInstrument(Instrument):
                 raise HostError(msg.format(output))
         if self.process.returncode != 15: # iio-capture exits with 15 when killed
             if sys.version_info[0] == 3:
-                output += self.process.stdout.read().decode(sys.stdout.encoding)
+                output += self.process.stdout.read().decode(sys.stdout.encoding, 'replace')
             else:
                 output += self.process.stdout.read()
             self.logger.info('ACME instrument encountered an error, '
diff --git a/devlib/instrument/energy_probe.py b/devlib/instrument/energy_probe.py
index b832d71..a817369 100644
--- a/devlib/instrument/energy_probe.py
+++ b/devlib/instrument/energy_probe.py
@@ -82,8 +82,8 @@ class EnergyProbeInstrument(Instrument):
         if self.process.returncode is not None:
             stdout, stderr = self.process.communicate()
             if sys.version_info[0] == 3:
-                stdout = stdout.decode(sys.stdout.encoding)
-                stderr = stderr.decode(sys.stdout.encoding)
+                stdout = stdout.decode(sys.stdout.encoding, 'replace')
+                stderr = stderr.decode(sys.stdout.encoding, 'replace')
             raise HostError(
                 'Energy Probe: Caiman exited unexpectedly with exit code {}.\n'
                 'stdout:\n{}\nstderr:\n{}'.format(self.process.returncode,
diff --git a/devlib/trace/ftrace.py b/devlib/trace/ftrace.py
index bfa3b5b..8e62ffa 100644
--- a/devlib/trace/ftrace.py
+++ b/devlib/trace/ftrace.py
@@ -278,7 +278,7 @@ class FtraceCollector(TraceCollector):
             process = subprocess.Popen(command, stderr=subprocess.PIPE, shell=True)
             _, error = process.communicate()
             if sys.version_info[0] == 3:
-                error = error.decode(sys.stdout.encoding)
+                error = error.decode(sys.stdout.encoding, 'replace')
             if process.returncode:
                 raise TargetError('trace-cmd returned non-zero exit code {}'.format(process.returncode))
             if error:
diff --git a/devlib/utils/android.py b/devlib/utils/android.py
index 0a9dfeb..4b43808 100755
--- a/devlib/utils/android.py
+++ b/devlib/utils/android.py
@@ -153,7 +153,7 @@ class ApkInfo(object):
         try:
             output = subprocess.check_output(command, stderr=subprocess.STDOUT)
             if sys.version_info[0] == 3:
-                output = output.decode(sys.stdout.encoding)
+                output = output.decode(sys.stdout.encoding, 'replace')
         except subprocess.CalledProcessError as e:
             raise HostError('Error parsing APK file {}. `aapt` says:\n{}'
                             .format(apk_path, e.output))
diff --git a/devlib/utils/ssh.py b/devlib/utils/ssh.py
index 3243708..9daa380 100644
--- a/devlib/utils/ssh.py
+++ b/devlib/utils/ssh.py
@@ -265,7 +265,7 @@ class SshConnection(object):
         # the regex removes line breaks potential introduced when writing
         # command to shell.
         if sys.version_info[0] == 3:
-            output = process_backspaces(self.conn.before.decode(sys.stdout.encoding))
+            output = process_backspaces(self.conn.before.decode(sys.stdout.encoding, 'replace'))
         else:
             output = process_backspaces(self.conn.before)
         output = re.sub(r'\r([^\n])', r'\1', output)
diff --git a/devlib/utils/version.py b/devlib/utils/version.py
index de37dce..1669a6e 100644
--- a/devlib/utils/version.py
+++ b/devlib/utils/version.py
@@ -10,6 +10,6 @@ def get_commit():
     if p.returncode:
         return None
     if sys.version_info[0] == 3:
-        return std[:8].decode(sys.stdout.encoding)
+        return std[:8].decode(sys.stdout.encoding, 'replace')
     else:
         return std[:8]