The sound that is made when someone sends you a chat message is not nearly loud enough. I have missed many a custom game because I did not here someone message me.
Even with the SFX volume turned up all the way, it is still too soft. The actual sound that is made is not very alerting.
The same can be said for the in-lobby chat (which is very important for team-comp setup) and for the ingame chat (although this is better).
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