diff --git a/src/webrtc/call.ts b/src/webrtc/call.ts
index cbc6390d15e..cfe94976d7b 100644
--- a/src/webrtc/call.ts
+++ b/src/webrtc/call.ts
@@ -47,6 +47,7 @@ import { CallFeed } from './callFeed';
 import { MatrixClient } from "../client";
 import { ISendEventResponse } from "../@types/requests";
 import { EventEmitterEvents, TypedEventEmitter } from "../models/typed-event-emitter";
+import { DeviceInfo } from '../crypto/deviceinfo';
 
 // events: hangup, error(err), replaced(call), state(state, oldState)
 
@@ -343,6 +344,7 @@ export class MatrixCall extends TypedEventEmitter<CallEvent, CallEventHandlerMap
     private callLength = 0;
 
     private opponentDeviceId: string;
+    private opponentDeviceInfo: DeviceInfo;
     private opponentSessionId: string;
     public groupCallId: string;
 
@@ -508,6 +510,17 @@ export class MatrixCall extends TypedEventEmitter<CallEvent, CallEventHandlerMap
         return this.feeds.filter((feed) => !feed.isLocal());
     }
 
+    private async initOpponentCrypto() {
+        if (!this.opponentDeviceId) return;
+
+        const userId = this.invitee || this.getOpponentMember().userId;
+        const deviceInfoMap = await this.client.crypto.deviceList.downloadKeys([userId], false);
+        this.opponentDeviceInfo = deviceInfoMap[userId][this.opponentDeviceId];
+        if (this.opponentDeviceInfo === undefined) {
+            throw new Error(`No keys found for opponent device ${this.opponentDeviceId}!`);
+        }
+    }
+
     /**
      * Generates and returns localSDPStreamMetadata
      * @returns {SDPStreamMetadata} localSDPStreamMetadata
@@ -792,6 +805,7 @@ export class MatrixCall extends TypedEventEmitter<CallEvent, CallEventHandlerMap
         // handler will start giving us more call events (eg. candidates) so if
         // we haven't set the party ID, we'll ignore them.
         this.chooseOpponent(event);
+        await this.initOpponentCrypto();
         try {
             await this.peerConn.setRemoteDescription(invite.offer);
             await this.addBufferedIceCandidates();
@@ -2052,9 +2066,10 @@ export class MatrixCall extends TypedEventEmitter<CallEvent, CallEventHandlerMap
                 },
             };
             const userId = this.invitee || this.getOpponentMember().userId;
-            const deviceInfoMap = await this.client.crypto.deviceList.downloadKeys([userId], false);
-            const deviceInfo = deviceInfoMap[userId][this.opponentDeviceId];
-            return this.client.crypto.encryptAndSendToDevices([{ userId, deviceInfo }], payload);
+            return this.client.crypto.encryptAndSendToDevices([{
+                userId,
+                deviceInfo: this.opponentDeviceInfo,
+            }], payload);
         } else {
             this.emit(CallEvent.SendVoipEvent, {
                 type: "sendEvent",
@@ -2351,6 +2366,8 @@ export class MatrixCall extends TypedEventEmitter<CallEvent, CallEventHandlerMap
         this.checkForErrorListener();
         this.direction = CallDirection.Outbound;
 
+        await this.initOpponentCrypto();
+
         // XXX Find a better way to do this
         this.client.callEventHandler.calls.set(this.callId, this);
 
diff --git a/src/webrtc/groupCall.ts b/src/webrtc/groupCall.ts
index fbcc3a8cf0f..f30b13447d7 100644
--- a/src/webrtc/groupCall.ts
+++ b/src/webrtc/groupCall.ts
@@ -58,7 +58,8 @@ export type GroupCallEventHandlerMap = {
 
 export enum GroupCallErrorCode {
     NoUserMedia = "no_user_media",
-    UnknownDevice = "unknown_device"
+    UnknownDevice = "unknown_device",
+    PlaceCallFailed = "place_call_failed"
 }
 
 export class GroupCallError extends Error {
@@ -653,7 +654,7 @@ export class GroupCall extends TypedEventEmitter<GroupCallEvent, GroupCallEventH
         return this.client.sendStateEvent(this.room.roomId, EventType.GroupCallMemberPrefix, content, localUserId);
     }
 
-    public onMemberStateChanged = (event: MatrixEvent) => {
+    public onMemberStateChanged = async (event: MatrixEvent) => {
         // The member events may be received for another room, which we will ignore.
         if (event.getRoomId() !== this.room.roomId) {
             return;
@@ -751,8 +752,23 @@ export class GroupCall extends TypedEventEmitter<GroupCallEvent, GroupCallEventH
         const requestScreenshareFeed = opponentDevice.feeds.some(
             (feed) => feed.purpose === SDPStreamMetadataPurpose.Screenshare);
 
-        // Safari can't send a MediaStream to multiple sources, so clone it
-        newCall.placeCallWithCallFeeds(this.getLocalFeeds().map(feed => feed.clone()), requestScreenshareFeed);
+        try {
+            // Safari can't send a MediaStream to multiple sources, so clone it
+            await newCall.placeCallWithCallFeeds(
+                this.getLocalFeeds().map(feed => feed.clone()),
+                requestScreenshareFeed,
+            );
+        } catch (e) {
+            logger.warn(`Failed to place call to ${member.userId}!`, e);
+            this.emit(
+                GroupCallEvent.Error,
+                new GroupCallError(
+                    GroupCallErrorCode.PlaceCallFailed,
+                    `Failed to place call to ${member.userId}.`,
+                ),
+            );
+            return;
+        }
 
         if (this.dataChannelsEnabled) {
             newCall.createDataChannel("datachannel", this.dataChannelOptions);