Dogs with sight problem aren't necessarily totally blind & deaf dogs aren't totally deaf, which is why a full medical health check is needed

Given he is responding to the slightest noise though, it seems unlikely he has a hearing issue.

Poor guy, sounds really stressed - and I bet you all are too

as others have said - try and stop thinking of 'pack' and stuff and think of him as an individual

Sounds like the move has stressed him a lot - from a nice quiet outside space to now being in a noisier invironment with everyone closer together
So I agree a crate to make his own den may help him no end (they can be pretty cheep, I got a really good one from ebay a couple of years ago for £30
You can teach a 'bed' command by chucking treats or toys (if there is anything he likes) in there - I have found the 'bed' command cuts tru my girls red mist when she cant respond to any other commands
Its not a punishment but you can send them to their safe den to calm down as its a nice safe place
I would also think about having him in a harness with a house line on if you are finding him turning on people and biting - that way you can get hold of him safley

as its clearly stressing him why not pop him in his crate or another room when people are coming in and out so he dosent have to deal with them?

As for his behaviour with your other dog, I cant say 100% without seeing things but collies are well known as 'fun police' splitting up dogs playing and trying to control things - just put him away if he is spoiling playtime
He may well have been punished for playing - or have decided himself playing is a bad thing - and it stresses him to see other dogs playing

I really do wish your parents will consider your idea for a behaviourist, someone helping you finally get inside his head may well mean you can all gain some understanding and love for him

Try leaving him with a kong as soon as somebody leaves the house, make him settle in the den he's already made for himself, you might find he relaxes a bit more. You could try sitting on the floor with him with the kong, get him interested, try some nice, gentle stroking, you want c-a-l-m and it is do-able. I have the nuttiest gsd ever but she can do the calm bit because I've taught her this is what I want, by doing what I've said above. It's now 2nd nature to her, that if one or both of us is going out, she gets her cheesy bone kong, goes into her bed and stays there, all nice and quiet until we get home.

I was in a similar situation to your parents, we've just moved house earlier this year, blooming builders etc. coming and going, something she's not used to, same as your dog isn't used to that, it just stresses them to the limit.

You really need to spend the time to actually teach your dog how to do the calm bit, otherwise, he just doesn't know what is expected of him. He's been used to being allowed to patrol the garden, now he's in another house, he's not allowed to do that, his mind is probably all over the place, as to what is exactly expected of him here, so it's unkind to just hope for the best and let him get on with it. Try and spend some time with him, being nice and quiet, on the floor, stroking him, I think he needs a bit of tlc, because what with everything else that's been going on, I bet he's been a tad neglected.....maybe??? I know he's been getting his walks etc. but that's not the same, as the rest of you getting on with your life and just expecting him to get on with his too when he really doesn't know what to do imo.

Good luck, don't give up on him, spend some time in the pet shop, get some difficult kongs, fill them with something nice, give him 5 mins of ball play here and there in the garden and see if you can try and calm him down a bit when indoors. Good luck, but I know what you're going through, it must be so frustrating seeing him so hyper all the time.

Perhaps if you tell us what area he is in, someone can recommend a trainer / behaviourist?

My totally deaf dog seemed to react to noise but in fact she was picking up on vibrations & dogs deaf or partially in one ear can & do react to very slight sounds, which is why the only way to test for hearing is a BAER test

I agree with both members ^^^^^^ also added facts are IMO moving house, with builders in and out...= stress.
I've had collies all my life and know they can stress at the smallest thing, it soon becomes an unwanted bad habit.

I think both the above members make valid points, your 20 and have moved back....maybe your parents could be persuaded to take your (or these) views on board and therefore your help could make their lives easier & that of the dog's...........please ask your Dad not to smack him it will only result in aggression xx

Not quite sure what the point would be? Our foster is almost totally deaf. I know because it's
obvious, she responds to hand signals and touch. No
Point doing a test.
For the dog in this thread, if it is responding to the slightest outside noise, as the OP has said, I think it's fair to assume his hearing is okay.