I have the same problem with my Aiwa stereo. Didn't realize the cam that moves the cassette deck's record/playback head into the cassette was driven by a belt. Are both decks set up the same way? I have a similar problem on the playback deck, only there the sound is muffled and the tape sounds for all the world as if it is playing in reverse, although the tape seems to be moving forward in the cassette itself.
I wish I had found this site a lot sooner than I did (I just found it tonight after doing a Google search using the model number of my stereo). My unit is now in a local repair shop, but I will be picking it up on Wednesday, January 17, unrepaired, as I don't know how much the repairs will cost (I live on a fixed income). I don't drive, either, so have made arrangements with the county's transportation service to get me to the repair shop and back home; they do not appreciate people undoing ride scheduling unless it is absolutely necessary.
Again, I wish I had known a lot sooner about the Aiwa CX-NA888's cassette decks' record/playback heads being driven by belts. Just out of curiosity, how much should it cost to have those belts replaced? If I had decided to go ahead with the repairs, would the cost have been very much, say on the order of $20-$30 or so, or would it have been more? I am also concerned about putting too much money into this stereo, as I bought it new seven years ago (and we all know, at least we should, how quickly technology becomes obsolete these days). I could purchase a brand-new system for a fraction of what I originally paid for my Aiwa unit; in fact, one of the technicians at the service shop I took my system to even asked me (over the telephone) to consider getting an entire new system before putting any large amount of money into mine, given the age of my system (which is basically why I eventually decided not to have it repaired). I have most of my CDs and even a few cassettes stored on my computer anyway (as mp3 files, using Audacity audio editor software), so I have little or no use for the cassette decks in my stereo at this point in time. I consider this my method of keeping up with the times, without spending a lot of money to do it.
Jeff Strieble, January 2007