distortion in one channel

I am looking for a suitable replacement for the thermally coupled transistors, in particular Q708, part number listed in the manual is:HT315672BO. I've looked online, and it seems like an old, obsolete part. Any help getting a substitute is appreciated. I've included below part of another thread...

I'm new to hifi repair and have become really engrossed with it's puzzles. I found a Technics SA-101 on the street last week and took it home out of curiosity. I need to give it a deeper clean but I don't think that's where my issues lie at the moment. When I got the amp, the right channel was...

Have an STA-77A that I'm stumped on. Right channel distortion, also seems heavy on Bass. Present on Tuner and Aux inputs. Mitigated when switched to MONO, but then distortion is shared with Left channel. Pin checked everything on the amp and pre-amp boards to compare components between...

Hi there, I have a nice and mellow Sansui AU417 but it has become temperamental i.e. it's happily playing both channels and then the right channel becomes suddenly & randomly distorted, so that I have to switch the balance knob to the left side only. This lasts for different lengths of time, and...

So I've cleaned this guy and replaced all the capacitors in the power supply section. I thought I finally had it working and it sounded great on headphones. I hooked up some speakers and it initially sounded good, but I've started to get an intermittent distortion only in the left channel. It's...

First of all, still learning things. That said, I have a Lafayette LR-1500TA that works - for the most part. I've recapped it and deox'd it. Gone through bias current adjustment and balanced the voltages. It sounds fine, up to mid-level. At some point as I raise the split-volume control...