Topic: Problem with difference between the channels

[piktstevs]

Could someone please explain the difference between the channels of my recordings and how this problem could be solved.  I have made about 15 recordings using this gear:  SP-CMC-8 (hc, low sens mod) > SP-SPSB-11 (no bass roll-off) > Tascam DR-40 [mic-in or line-in]. All the recordings have visually stronger but audibly weaker and more muddy signal in left channel.  Besides this channel has audible digital noise (see the picture below). The same problem, just without digital noise, remains then I use line-in.

I am sure that position of the microphones and mobile phone has nothing to do with it. Could it be:

-          Problem with microphone capsule?
-          Defected Tascam DR-40 1/8 jack input? Maybe I should try to clean it?
-          Defected SP-SPSB-11 1/8 jack input or output? Maybe I should try to clean them?
-          (…)?

Thank you.

Audio sample: http://www.mediafire.com/listen/nodly085mj555dc/Sample.wav (9MB)