Front pass side speaker going in and out

So I put a system in my truck a while ago and somewhat recently (within 4-5 months) I noticed it sounded weird and confirmed the front passenger side speaker was going in and out. Thought it could’ve been a blown speaker so before I replaced it I checked all the wiring connectors and that was all good. Crutch field was awesome enough to send me a replacement for free with a return label for the old one. I replaced it and it still goes in and out so now I have to chase this issue. To answer possible questions: yes it’s only the front passenger door speaker, tweeter works and rear works. Goes in and out randomly. There is the slight possibility that it goes out when I press my break but it dosent 100% seem that way. I have a taco tunes amp with taco tunes amp rack and plug n play kit to amp all the speakers with the oem wiring. All other speakers sound good and work and sub too. And idk if the other speakers are making up for it when it’s up high but it almost sounds like it Dosent go in and out when above volume 28 ish around that area.. So what do U guys think it could be. Connector? Grounding issue? Taco tunes issue?( I’ve heard horror stories about the company but lucked out with my setup(so far))

 

Anyone?

 

A) bad amp
B) intermittent short in the wiring to that one speaker.

My guesses.

For fun switch the left and right inputs (downstream of the amp first, then upstream) see if the problem shows up in another speaker.

 

Well, when I was replacing my OEM speakers I figure out my wiring to passenger front door speaker
is broken, sound going on and out, really weird, when in the middle of phone conversation...
Ending up replacing broken wire, all good since then.

 

Doesn't the 6x9 wiring go from

HU>tweeter>speaker?

So if the tweeter is working, it could be from the tweeter wiring to the speaker

 

Yup, door speaker is downstream from the tweeter.