I have a sony str-de675. Compared to things today it is relatively old. Last night I noticed that my right speaker was very faint. I adjusted the balance which did not work. I switched speakers so I kwow it is not the speaker. I reset the receiver per Sony and still nothing. Does anyone have a suggestion as to what the problem might be or how to resolve?
Your options are to have it repaired or to replace it. If you have an old style repair shop in your area, they might be able to repair it for very little as a labour of love rather than anything else. If there is no such thing in your area, you have but one option left unfortunately.
"Look in the craiglist for receivers like luxman R117, R115, Tandberg, Marantz, sansui, old Yamaha CR-series."
Consider that none of those receivers can easily be repaired when they break and repairs will cost more due to the conditions you'll be placing yourself under.
The few companies on that list that still exist in the US do not support their older gear - many of them are not even owned by the same parent company nowdays. The others - Tandberg, Sansui - do not exist in the US. The only way to get any of these products fixed is to search out someone willing to work on vintage gear who also happens to have a spare of whatever you're trying to fix to pull from for parts. Then you are still putting 20-30 year old parts in a repair.
This isn't a totally unrealistic suggestion but you should know going in there are some real hurdles to buying this sort of product..
For HT, you can get a factory-refurbished harmon kardon avr-254 for less than $250 on ebay from the harman Audio store. I'm sure there are lots of very affordable receivers that would suit you just fine as well. There's no need for you to spend a huge amount on it.
"Look in the craiglist for receivers like luxman R117, R115, Tandberg, Marantz, sansui, old Yamaha CR-series."
That's true that these old gears will not last you as long as a new one - but you will be enjoying more quality for the price of the sony you own. If you were to buy a new one at the level, you would be paying a lot more.
That's why it will be a good idea to buy it on the Craiglist then on ebay - you can take your speakers and test it before you buy.
If it works, it will probably give you years of good service. If it breaks down, you still didn't lose that much money still - and you can get another one.
If you are looking for a newer one, you can also search for these companies.
Arcam, creek, rega, onkyo A-9555, etc.
As someone already mentioned, you don't have to pay a lot at this point to enjoy some good sounds - but when you upgrade the receiver, you might want to upgrade other parts of the system.
If you do, for a few hundred $, you can assemble a system that is quite enjoyable - if you ask questions on this sight, and get some info.
I left out an important company in mid-fi - NAD. There should be many receivers and integrated amp by that maker - and they do sound better than your sony.