NAD 3020A Integrated Amp

So I have a series of questions re: a NAD 3020A I just bought on Ebay. I'm just getting started on trying to build a good system so please excuse my lack of knowledge.

1. NAD 3020A Amp hooked to JBL 4312A Control Monitors and new REGA RP-1 Turntable. NAD is replacing a early 90's Sansui RZ-1000. I would have thought there would have been an appreciable difference in sound quality but I'm not sure that there is. Can't tell if it better, worse or just different.

2. NAD delivers a electrical snap sound to the speaker which Sansui did not. Is this cause for concern? Should I have this unit tested / looked over?

3. As this is an older amp it has limited inputs. Is it ok to run IPOD or DVD into the AUX input? Also no CD input, any ideas?
my parents pops as well, it has done this as long as I can remember and should be no problem.
The speakers are probably revealing the flaws of the NAD. The NAD has a dry sound, and also lacks transparency. I would try a better amp myself. I think people liked them because they didn't have the solid state harshness, that a lot of other budget amps had in it's day. I'm not trying to be rude, but I think the rest of the system could do better with a different amp. I'm not familiar with that Sansui either.
The caps in that Nad are good 30 years old, generally the life of caps is about 15 years before they start to wear out and change the sound of a particular amp. The real character of this little beauty may not be what you are hearing so making a judgment after 30 years on the sound of the amp is kind of unfair.

In its day it was a great sounding amp and I had the pleasure of listening to one brand new bought by a very close friend who continued to own it for next decade or so driving his Wharfrdale Diamond initially and later the Wharfdale E40's. I had owned the Nad 3225PE which essentially was the same amp albeit with "Power Envelope" circuitry incorporated.

The Nad 3020A was the poor audiophiles integrated amp as I remember it being dubbed by the press.

Just my 0.02
Do you know if it is possible to replace the capacitors or is that prohibitively expensive to do? I love the design of this amp and a lot of the NAD stuff esp. from this era, so I'd like to stick with it. Looking for a NAD tuner now as well.
Iamnate, most likely not all caps need replacing, just all the electrolytics. Unless you can get a copy of a service manual to identify their location and values and have some de-soldering and soldering skills, you will be advised to find a tech to do this. The labor will be much more than the parts cost.

I have a 3020A I use in with my TV. I replaced the speaker spring clips with mini-binding posts and that is also recommended.