NMEA sentences with unexpected characters

I'm using python to read data from a u-blox NEO-M9N chip via i2c on my raspberry Pi.

For the moment, I haven't built the rest of the script but I'm a little confused by the output of the chip as it seems to include characters that don't belong there, such as °,¬, or Á. Sometimes those seem to be replacements for characters that look alike: 021120 is correct for a few lines and then is replaced by 0²1±20, which is not too far away.

The sentences might be correct for anything between 5 to 50 lines and then I'll get something like this (I've replaced part of the GPS coordinates with X but you get it):

$GNRMC,204107.00,A,XX.20¶46,N,XX.47371,E,0.844,,021±20,,,A,V*17
$GNRMC,204108.00¬A,XX.20603,N,XX.47454,E,0.921,,021120,,,A,V*1B

Any idea to what this could be due? I'm very sure this will mess up what I want to with the data afterwards...

Here the code I'm using to read the data:

import time
import json
import smbus
import logging 

BUS = None
address = 0x42
gpsReadInterval = 0.1
LOG = logging.getLogger()

# taken and (poorly) adapted from
# http://ava.upuaut.net/?p=768

def connectBus():
    global BUS
    BUS = smbus.SMBus(1)

def parseResponse(gpsLine):
    gpsChars = ''.join(chr(c) for c in gpsLine)
    if "GNRMC" not in gpsChars:
        return False
    
    print(gpsChars)

def readGPS():
    c = None
    response = []
    try:
        while True: # Newline, or bad char.
            c = BUS.read_byte(address)
            if c == 255:
                return False
            elif c == 10:
                break
            else:
                response.append(c)
        parseResponse(response)
    except IOError:
        time.sleep(0.5)
        connectBus()

connectBus()
while True:
    readGPS()
    time.sleep(gpsReadInterval)

For posterity, someone has solved it for me: Fix special characters with closest equivalent without map

It is indeed a hardware issue but it can be fixed via software using this guy's answer