After M15A (3310) is started, the motor rotates, but there is no audio output. It needs to be turned on and off several times before there is audio output.
After there is sound, the playback and recording performance in 38/S is perfect.
But only 19/S only L channel is normal, R channel sound is very small, but switch MONO/stereo switch, R channel returns to normal. I suspect this is related to the above problem, but I don't know where it is.
In addition, if I swap the left and right playing cards, there will be no sound output. The numbers of my two sound cards are different. One is WV1 and the other is WV11. Initially, WV1 is inserted in position 1. It was normal before I swapped the positions of WV1 and WV11.
Q, where should I check? It seems that everything takes only one step.

Thank you!