The backstory:

Fairly recently I bought a Pioneer DDJ-SX from a friend it was 3 years old and he was offering it at a good price. I had issues with it crashing along with the early signs of fader bleed. He said he never had any issues and I believe him however I decided to get another slightly newer 1-year-old DDJ-SX (bedroom use only, hardly used, always dustcovered according to the seller) to see if that solved the issue. It didn't but after reinstalling windows & rolling the Traktor version back to 2.6 which is what I had before the 1 year old one works perfectly. Well the software does.

I didn't notice any real issues with it for a few weeks, but I had noticed a slight drop in volume occasionally, I thought this was an XLR issue so I swapped the cables over. Seemed okay for one gig then the next the same again but slightly more dramatic (from 12 o clock to 11.30 maybe), I checked the XLRs and they seem to be good at the connectors. I experimented a little and it seemed like it only happened when I rested my hand on the metal casing? So today I 've tried every knob everything to find an issue and now I've noticed that the channel 3 fader bleeds... AHHHH !

Where I'm at now:

I like the DDJ-SX, I use Traktor so being a Serato controller it's not perfect but it's the "best" controller I've used. Do I get another NEW DDJ-SX maybe the mk2 and hope the faders don't bleed after a year?
Do I get this one repaired, and then possibly have the other faders / pots go sooner or later?
Or do I look at another controller entirely.

I'm looking at the Traktor S4mk2, S5 & S8 and Denon MX8000. Considering I have no intention of using remix decks the S8 seems overkill, I always plan to use a laptop so Denon's controller also seems overkill. Which leaves me thinking mainly about the S4 & S5... Both cannot be used standalone?

Maybe Benny or other S4/S5 users can help me out here:

A) If Traktor crashes what do you do?
B) Can you plug an external source (phone, laptop) via RCA into the unit and should traktor crash play from this source?
C) Is the microphone on it's own channel?

It looks like the S8 does everything I would want ... but it's twice the price and has loads more features I will never use.