Newbie Troubleshooting Question

OK... So I got a $12 Kenwood preamp (no kidding) and even though it was more modern and quiet, the sound was not as good as the Hafler DH-101. Don't ask me to explain it but the Hafler just had a better sound. At any rate I think I want to keep the Hafler but it has a hum in the right channel that you can hear at low volume levels which is where I do most of my listening. It is only in the right channel. Also there is some hiss with the volume all the way down. Additionally the sound will not turn all the way down like maybe a bad pot or something. The balance was off which is part of the volume control but loosening a hex bolt and repositioning the knob took care of that problem. I have found some places on the internet that will go through the unit for $150 to $300 but I hate to pay somebody that much just to replace a resistor or capacitor.

My question... Does anybody have any suggestions on what I might look for or do to eliminate this problem? Is this a common problem with an easy fix? I could probably replace a resistor or a wire but even that would be at the far limits of my expertise. I always worry about getting electrocuted by a capacitor or something. Now I did open the case up the other day just to see if there was something obvious like a loose wire or something but didn't see anything. The unit did have a glass type fuse by the power supply which looked like it had a resistor inside of it. Never seen that before. So if any of you have any suggestions I would greatly appreciate it. I already tried the previously mentioned suggestions. (Thanks RWWEAR & DGAYLIN)
Thanks in advance for any help or advice you might have.

The capacitors in the unit are past the 20 year old mark by a very comfortable margin(going on 30). No doubt- Ripe for replacement. I'd start with the power supply caps. Were you provided with a manual when you bought the unit? If not- Buy one on eBay. That will give you a complete list of parts, and the full construction instructions that originally came with the piece. The circuit board was pre-assembled, but the parts layout, and schematic are included in the manual. Then too- A few people offered power upgraded power supplies for the 101. Some are still available. Here's something on eBay that may interest you: (http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=260359603612&ssPageName=MERCOSI_VI_ROSI_PR4_PCN_BIX&refitem=260350575646&itemcount=4&refwidgetloc=closed_view_item&refwidgettype=osi_widget&_trksid=p284.m185&_trkparms=algo%3DSI%26its%3DI%26itu%3DUCI%26otn%3D4%26ps%3D42) BTW: The S/N ratio was high enough that no hiss should be audible, especially with the volume turned down. I was the Hafler dealer in Orlando/Winter Park, FL for a few years, and used the 101(modded) in my demo system back in the day(early 80's). No noise at all would have tolerated in my audition room. RE: The power supply fuse- That's just what some slo-blo fuses look like. RE: Getting electrocuted by a cap- The voltages in a SS pre-amp are too small to worry about. If you can solder, you can handle the DH-101 upgrade. It would be a great way to get involved in the DIY electronics/modding hobby(It's highly addictive).

Thanks for the advice Rodman. By the way I used to live in Orlando before I moved to the Dallas area. I had seen that kit and another on that website. Do you think this kit would eliminate the hiss and the hum? I'm thinking the hum is from a loose ground related to the right channel, but what I know about electronic circuitry wouldn't fill a thimble. Gosh I hate being so stupid about something that I know is ultimately very simple. I would probably end up soldering one of those parts in backwards and frying my preamp, amp and setting the house on fire. There's an electronic shop down the way from me... Maybe I could get one of those guys to put those pieces in for me. I don't think it would take more than about 20 minutes to do.

I actually have the assembly/owner's manual I found somewhere on the internet. Anybody wanting a copy can send me a message and I'll email you a copy.

P.S. Free Download of Hafler Manuals Here:
http://www.hafler.com/techsupport/index.asp?ID=3

Well I opened the preamp up, inspected what I could, moved wiggled and jiggled and the hum dropped about 90% which I can live with for now. I hooked up the Kenwood preamp I paid $12 for the other day thinking the sound difference wasn't as vast as I had imagined and could give the Kenwood a second chance. Guess what? I was wrong! It's amazing how much difference in sound there is between the two. I swear it's like night and day. The Kenwood is quieter at low volumes but the sound difference is drastically worse than the Hafler. It's hard for me to understand that there is as much difference in sound quality as there is because I'm certain that the Hafler is not in 100% working order. Maybe I should send the Hafler and have it completely rebuilt. Are newer designs markedly better sounding than a 23 year old Hafler that is in good working order. Maybe I should just plunk down the cash for a new preamp and forget about worrying about worn out capacitors etc. Hmmm....