Obviously, any brand can have a quality defect, but I'm thinking that the statistical probability of getting back to back units with the exact same defect is probably pretty slim. I think cusco69 is barking up the wrong tree with the "cheap parts" and "common issue" claims as well.
My guess is that there's something else happening, but I'm just not experienced enough with the ways of electricity and power generation to give any tips. But there are some very smart people on this forum who've dealt with ground hum and RF noise and the like and can probably offer some ideas. It may not help in this case, since you've already returned them, but the knowledge may be helpful for future situations.
My guess is that there's something else happening, but I'm just not experienced enough with the ways of electricity and power generation to give any tips. But there are some very smart people on this forum who've dealt with ground hum and RF noise and the like and can probably offer some ideas. It may not help in this case, since you've already returned them, but the knowledge may be helpful for future situations.

