#1
I got my guitar back from the shop because It was in repair and was getting chrome humbucker placements on it. It's an SG-310, Anyway when I took it home I noticed something theres a overdrive effect on my two low strings and a buzz but also when I turned on my BOSS-DS1 it was a lot quiter even on full volume so there was a jump in clean and distortian however it had a lot more distortain. I'm taking back tomorrow but I'm asking for what you guys think. (No "The guys that work there suck" posts)
#2
it sounds like they've put very high output pickups in it, which are overdriving your clean sound (or overdriving the buffered bypass in your DS-1), and pushing the dry signal up beyond the volume the DS-1 can put out so that it can't reach unity gain, hence the drop in volume. What pickups did they put on the guitar?
Rig Winter 2017:

Fender Jazzmaster/Yamaha SG1000
Boss TU-3, DS-2, CS-3, EHX small stone, Danelectro delay
Laney VC30-112 with G12H30 speaker, or Session Rockette 30 for smaller gigs
Elixir Nanoweb 11-49 strings, Dunlop Jazz III XL picks
Shure SM57 mic in front of the amp
#4
so all they did was put chrome pickup covers on it? it seemed like you said they replaced the pickups

it seems like what they did, if they just put covers on the pickups, was probably change the height without realising as a result of having to remove them to put the covers on - try lowering them by turning the little screws either side anti-clockwise a little and it should clean up the sound and also reduce the output so the DS-1 will be able to match the volume. if this doesn't work, then it's probably best to take it back to the shop and get them to sort it out for you.
Rig Winter 2017:

Fender Jazzmaster/Yamaha SG1000
Boss TU-3, DS-2, CS-3, EHX small stone, Danelectro delay
Laney VC30-112 with G12H30 speaker, or Session Rockette 30 for smaller gigs
Elixir Nanoweb 11-49 strings, Dunlop Jazz III XL picks
Shure SM57 mic in front of the amp