Strange sounds coming from my speakers.

25 years, eh? That's a pretty good run. BTW, 25 years ago, a Roksan Caspian Integrated amp and Ruark speakers was a pretty darn good system. If it's been well cared for and is still in operational condition, I have no doubt it is still an enjoyable system.

And yes, I've heard things from my system that made me go check the door to see if someone was there, to answer the phone, etc.

Is your 25 year old system still in good condition? Have you ever need a repair in that time? BTW, the capacitors in you integrated amp may be degraded a bit by this time. Usually replacement of the caps is the only maintenance need on an older amp. If you happen to know a competent tech or repair shoppe, you may want to ask them about it. Then again, if everything still sounds fine to you, you may not want to bother....... 

@reubent 
Thanks for reply yes everything still sounds great,as good as it did ,no i have not had any probs with it as it has laid dorment for about 15 years with kids not bothered now growing up brought it out of retirement .The only thing that does not work anymore is the cd. I have got a squeezebox with an old Sherwood cd player.Thinking of sending it back to roksan.What do you think probably a small fortune.

cobbone1
It sounds like you hit on the right combination first time around and got a very resolving system. After many changes and tweaks, I've got to where, with the proper recording, I look around to see if someone is in the room or are startled by what is in the recording, thinking it's coming from an open window or door, only to find it's just what I'm listening to. 

No need for that white van to come around, unless it's some meal you ordered. 

All the best,
Nonoise

@cobbone1 - CD transports do fail over time. Do you happen to know if it is a problem with the actual transport mechanism or laser? If so, you might want to ping @georgehifi . He has provided the OEM model part numbers to several forum posters when they needed replacement CD drives/lasers. Of course, you can check with Roksan also. They may have used an inexpensive OEM CD drive/laser assembly that may be relatively inexpensive to replace. It sure would be cool to have a complete working Roksan Caspian stack if the repair were not too expensive.

Well done. Even if the amplifier may not have seen that much use, replacing the elektrolytic capacitors could still be a wise precaution, if you can find an affordable maintenance engineer. Personally I would not bother with the cd player. Either you move over to streaming completely, or buy an affordable Bluray player with analogue output. That way you will also have the opportunity to watch movies with decent sound.

Just get the Roksan recapped and serviced as other have suggested.

Happens to me all the time, not just me but guests too. Wasted much energy getting on my feet to check the door or the kitchen, garage etc. I really hate it when I'm jamming and a guest says I think there was a knock on the door or they turn their heads and look behind them.