Yes. Same issue. Bought Sony xm4 and tried all my Wiim products BY out (mini, pro & ultra) but after usually 10 mins of perfectly fine use the xm4 started to play up …. Distorted sound, unlistenable. Informed Wiim of the issue and returned the xm4’s. Wiim never provided a reason or solution.
It’s reassuring that others have had the same issue….shame as I liked the xm4’s but as my use was intended with Wiim products, they had to go back. Now not willing to risk another BT headset.