Tascam 414 not working completely well. sounding lower and getting noises

[donaugustoluna]

Hello I am new at this. But I do love home recording. For any spanish lyrics lovers and south america folk rithms, check my songs at https://soundcloud.com/augusto-luna-cantautor/
ok enough of me. the machine:
My Tascam414 is recording TOO low on track 2. it sounds well, while recording, but at playback I discover the sound is too low, as if it was recorded with TRIM at line (while using a mic, but actually I am having the TRIM at MIC for decent levels) . Plus, the track 4 is making "turntable-like noises" when I have it on SAFE and in OFF, and recording on some other track. BUT when I put track 4 in "4"position (like for recording), I don´t get that noices anymore (only way of recording in other tracks with not any noice busting my balls). PLUS it seems like, when recording on tracks 1, 2 and 3, the sound level when recording is good, but at playback is lower, and the color lights dont act the same, they show lower levels also. any guess on how to fix this? any Diy thing like cleaning some part? thank youuuuu

 

[A Reel Person]

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You should start by cleaning the heads with alcohol and swabs. I'd also look into demagnetizing the heads with a demag wand. A magnetized head might produce clicks and pops on playback, possibly affecting the output, but a dirty head could affect output and recording levels.