I bought my first decent HiFi about 18 years ago which was the Nap150x and Nac122x which has never been serviced but works faultlessly, over the last year it seems to be loosing the clarity it once had. I know these are entry level but looking at new which is a bit out of my price range I wondered if this is actually worth sending it in for at least a full service and possibly an upgrade or is it too entry level that I would be wasting my money?
Any info would be greatly appreciated.
If you are in the UK, then you could consider sending them to Class A in Sheffield who will do a Naim approved service a little cheaper than sending to Naim
FYI These are the recommendations for service intervals:
Olive (circa 1989 - 2000) every 8 - 10 years
Newer Black products (2000 - present), every 12 - 15 years
The 122x and 150x are great products and well worth servicing. As suggested above, send them to Class A in Sheffield, which will be cheaper and quicker than Naim doing it. I once had a 122x and 150x and loved listening with them. If you can find £300 or so under the mattress, get a Flatcap 2x to power the 122x. It will give a really significant improvement, so long as that too has been recently serviced of course.
I agree the NAC122x is a bit of a gem and is an excellent pre-amp, in my view, the best of the shallow box units. I am a little less enthusiastic about the 150x and would rather couple the 122x with a NAP200, that sounds great together. Both of the OPs units well worth servicing, though.
A flatcap XS would be a great addition too.
Yes, servicing is essential and will cure the malaise you have identified. My 32.5 (1987) has just had its second service and sounds wonderful even powered from a NAP200 (also recently serviced)!
Hi, Please get both boxes serviced, that’s nice gear.
I recently had my NAC152XS preamp serviced and was very pleased with the subsequent drive and clarity of the music.
The advice of others to find a FC2x and then service it, is sound too. That’s the Naim forum, always spending other people’s money 
I remember the day I had a FC2x added to my 122x/150x. It’s one of only two occasions when I’ve literally laughed at the scale of the difference that an upgrade has made. It’s surprising what the FC2x adds, especially considering that the case is largely empty space. The other occasion? Moving from a 252/Supercap to a 552.
Thanks for all you reply’s, it definitely looks like I will be sending them in. I have emailed Class A in Sheffield, we’ll see what they come back with. I will keep you posted.
Well I took all your advice and purchased a used Flatcap2, that has already lifted the sound. I also sent Class a a couple of emails as they did not answer, they finally did and I had a few more questions, I haven’t had any reply’s to those, but I did contact jjThatcham and he came back within a few hours with all the answers which made me think of a few more questions about upgrades, all replied to and I have put my name on his list as it will be a few months as he has a lot of work. The upgrades and servicing won’t be cheap but certainly cheaper than a new system and hopefully a noticeable lift in quality. Thanks for all the info, greatly appreciated.