HDMI problems may be more to do with the graphics hardware drivers. I don't have problems with my nVidia card, using the nVidia drivers rather than open source. It's an option on install. I use an old TV and output sound though the TV speakers. I had sound problems with Mint 19.2, occasional loss of settings, wasn't a big job to recover. It's maybe too early to say whether Mint 19.3 has fixed it.