Negative relationship with 9 year old son

[MintGreenPolo]

My relationship with my 9 year old ds is really bad, he is so rude and disrespectful to me. To give an example I walked into the room as I heard him and my 11 year old fighting and I asked what had happened and got told to shut up by my 9 year old. Of course he was disciplined but this is a regular occurrence and disciplining him doesn’t change anything. He is rude to me all the time. Daily almost. He has no respect for me and just speaks to me like shit if I’m honest. I don’t know where to go from here?

I don’t like being around him if I’m being honest.

How has it come to this?
Disrespect doesn't appear out of the blue. What has positive relationship building been like for last 9 years? Do you admonish only or use positive parenting too?

He has definitely not always been like this it’s been a recent thing but yes I do discipline him when he is telling me to shut up.

Of course. You can't have him behaving badly without push back.
I meant a warm loving relationship needs positive elements to be part of the scene too. Sometimes in a busy life it's easy to react to bad behaviour but forget to notice and build the good. Sometimes when kinds behave well is just a relief and goes without comment.
If he's not always been this way, maybe the warm loving side of things had been neglected/eroded away.
Or maybe there is something else going on, bad example from older kids he looks up to for insurance.

Instance.