Shanling MW200 channel volume problem

I have been using the MW200 with my TIN T3+ for the better part of a year now and loving the experience, I went to use them last week, turned them on just like I always do and noticed the left channel was significantly quieter than the right. I checked the balance in the Shanling app and saw it was dead center, in order to get the channels to sound even I need to push it nearly completely to the left side and even then the low end sounds a little lighter than the right.

I’ve tried the IEM’s with the stock cable plugged in to my laptop and they sound totally normal. There is no visible damage to the MW200, no breaks or cracks in the cables and no drops or accidental damage that I know of that preceded this issue.

I know not many people may have a lot of experience with this thing but I am wondering if anyone has run in to this issue or has any advice for how I should proveed.