How to hard reset a sony str-DE898

Troubleshooting for 'No Sound', but you probably need a Sony Service Centre.

https://www.google.com/search?q=Sony+STR-DE497.+Has+no+sound

..

they are located inside the unit next to the power transformer but be careful of the dangeroud voltage

There's a Speakers OFF/A/B/A+B button on the upper left front panel. Press it a few times and watch the display.

wow look on amazon ratard

Most likly bad solder connections on the display board. Look for solder rings on the LCD. You must remove the front panel to gain access.

This sounds like a very poor connection. Please make a new splice on speaker and receiver. This should take care of this for you.

Check the fuse, Sony is known for its random problems with sound. The one I have you must tap it on the side. Its a flicker switch inside.

I understand that you have tried connecting different audio source to the Receiver as some of the audio source will output only 2 channel audio. I hope you have tried changing the Input mode and Input selector to get the surround sound.
Please disconnect the speakers with the receiver and clean the edges of receiver and speaker cables using solution like alcohol and try.
If the issue persists, please interchange the rear speakers with front speakers and vice versa and check if audio is coming to make sure that the speakers are working fine.
If the audio comes after replacing the speakers but not from surround speakers, the receiver requires service.

Reset can mean many things... Input/ output/surround/ or is it saying "Protect" on the display?
If that's the case, unplug, wait a minute, plug it back in and turn on. If it still say's Protect, disconnect the speaker wires and test again. Chances are you have a shorted wire or speaker. If you need something different, post a reply and I will help you further. Hope this helps

Just fixed it, The Optical cable wasnt properly plugged in on the other end.

Found the fix here:
http://esupport.sony.com/US/perl/model-home.pl?mdl=STRDE945&LOC=3