✔ 最佳答案
The testing procedure as follow:
1) Contious play a muisc which make both of the speaker have sound.
2)plug your speaker into the sound card, to see the result, you may also try to pull out the speaker's a little bit ( not completely pull out, try difference contact point)to see the result, if it is still not working, I think your sound card's phone hole may be damage or bad contact, you may need to contact the maintenance or replace a new one.