Radio has constant crackle and squeele?

Something in the antenna system. Coax or antenna shorted to ground would be my first guess... try a new piece of coax directly from the radio, to the antenna

 

Does it vary with rpm when parked? Does they still have them same issues when the engine and all other accessories are powered down?

 

Check this with an ohmmeter and get back to us..

 

just got rid of that problem yesterday finally the 2015/2016 trucks have the cb and stereo system tied into each other. that crackling and squeal you hear is actually because.if you listen closely when you transmit your cb is going thru the stereo speakers aka 6x9 up top. I grounded everything on truck. but the short of it is. go buy the cobra s500 ext.speaker turn the talk back crap on speaker off. push the noise cancelling button in. its really really bad if you run a radio with a built in amp in it. I run either my magnum s980 with a 300 watt amp under its belly or I switch and run my galaxy 98 v. with a amp under its belly. I went thru hell getting rid of that problem. do not cut off that red wire off the back of that ext.speaker repeat do not cut the red wire in the back of that ext. speaker. leave it intact.

 

and so you perfectionists and you know who u/r . the red wire is for a ear plug for the driver if he's running team. which I don't do because I'm not going to prison for killing some idiot .

 

Ok here lets do a couple troubleshooting questions before we assume something.

First is this ... When you listened to the radios, did you have the truck running?

Second ... What does the crackling sound like? I know this can be a stupid question but there are different sounds.

Third .... Does the crackling on receive happen when the squelch is turned up or the rf gain turned down?

Fourth .... When transmitting, is the mic gain all the way up (don't remember if the 148 has a mic gain) and if it doesn't is the mic a power mic?

And more important question that I should have asked right from the start is this, has either these radios been modified or messed with like a peak and tune job?

 

and I know what everyone is thinking just shut off the stereo. it makes no difference your cb is always going to come thru the door and 6x9 speakers. my truck has no visible cb antennas on it factory I mean. the factory antenna is up in the top back of the cab .real dumb ### who came up with that crap !!!!!!!

 

I disconnected the factory stereo system in all of the Volvos that I used to drive and that solved my problem since I don't use a stereo to begin with

 

here's the kicker with this setup per freightliner themselves aerodynamics----it just makes me feel so good inside to know how much fuel I'm saving because those two whip antennas are not out there blowing in the wind