Have you flashed the repack? Let us know in the comments if your ping improved or if you ran into the "boot loop" issue on V2 hardware.
Flashing a "repack" or the wrong regional firmware (e.g., using ME_1.30 on an Indian version router) can the device. Proper Installation Steps D-link Dsl-2750u V2 Firmware Me-1.30 Download %5BREPACK%5D