Should work for both RP1 & RP2.
I have fixed my own speaker glitches this way. But I do a lot of stuff to my phone, and my issues could have came from that and yours from elsewhere.
Also, I should mention for the sake of information, that my speaker audio glitches happened most while doing things like watching a movie or playing a game with Dolby on. Might be obvious, but I've seen others say their glitches happened at other times too.
I just thought I'd offer this advice on the chance it's not more hardware related on your end.
Try this:
(Again, I don't use GSI ROMs, but this should work for those who do, also.)
Yank the vendor.img from the dev files on the RAZER site that are the appropriate update number and current os for your device. Example, Mr1, 2 or 3, for pie (9) or Oreo (8) for rp1 or rp2, etc.
(GSI users should grab the vendor image that relates to what your phone was running directly before your put a GSI on it)
Place the img on your phone.
Force close Dolby, then Clear Dolby cache and storage.
(I don't use gsi's so, idk here. You can probably skip this part, as you don't have dolby system side, but it was part of what I did)
Directly Reboot into TWRP.
Flash vendor.img to vendor partition, by choosing install then image instead of zip. You can also use fastboot.
Clear art and dalvic caches in recovery.
Now you can reboot into your OS.
(I like to wait at least 30 seconds after booting, before doing or checking things. Android is still doing some background stuff after it visually looks booted)
See it it worked for you, fingers crossed!
I Hope it did!!