I just receive this technics su-g91 amplifier and i was trying to hook up my surrond sound but only my center spreakers are working..what am im doin wrong

Check the Technics website, or Panasonic, as Technics was made by Panasonic.

TECHNICS SU G91 STEREO AMPLIFIER

I assume you want to use the SU-G91 as a power amplifier to drive your speakers. If your receiver has connections for inserting an equalizer (may be labeled pre-amp output and power amp input), remove the jumpers between the pre-amp and the power amp, then run cables from the pre-amp to the SU-G91 inputs. You can have an equalizer between the receiver and the integrated amplifier.
If this is not available, use the recording output (for a tape recorder on older receivers). Note that the volume control on the receiver will be bypassed with this connection.

Hey, The model of the amplifier is SU-G91 Technics.....If you could help......Thank you.

THe amp has detected a problem and shutdown to prevent further damage. This unit has 2 amp pacs inside and one or both have failed. If you can solder, you can fix this yourself. The main amp pac is an SVI3206 and can be purchased online for about $60.

Keep me posted.
Dan

Have you checked the fuse in the unit?

Did you ever find the solution to the left channel issue? I have the same problem with mine.

I had the same problem. As soon as the volume reached about 24db it would go into overload. I was able to fix it by soldering all the connections on the larger power module. The one connected the the heat sink. When I took it apart there where several solder points that had come loose.